Removal: GraphQL field take_ownership_pipeline_schedule
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For guidance on the overall deprecations, removals and breaking changes workflow, please visit [Breaking changes, deprecations, and removing features](https://about.gitlab.com/handbook/product/gitlab-the-product/#deprecations-removals-and-breaking-changes)
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### Deprecation Summary
<!--This should contain a brief description of the feature or functionality that is deprecated. The description should clearly state the potential impact of the deprecation to end users.
It is recommended that you link to the documentation.
The description of the deprecation should state what actions the user should take to rectify the behavior. If the deprecation is scheduled for an upcoming release, the content should remain in the deprecations documentation page until it has been completed. For example, if a deprecation is announced in 14.9 and scheduled to be completed in 15.0, the same content would be included in the documentation for 14.9, 14.10, and 15.0.
**If this issue proposes a breaking change outside a major release XX.0, you need to get approval from your manager and request collaboration from Product Operations on communication. Be sure to follow the guidance [here](https://about.gitlab.com/handbook/product/gitlab-the-product/#deprecations-removals-and-breaking-changes.)**-->
Deprecate the `take_ownership_pipeline_schedule` GraphQL field in [graphql/types/permission_types/ci/pipeline_schedules.rb](https://gitlab.com/gitlab-org/gitlab/-/blob/c6736f63d55c6d1df45bd9653a4a7d8cccf147e1/app/graphql/types/permission_types/ci/pipeline_schedules.rb).
Use the `admin_pipeline_schedule` field instead, to determine if a user has the ability to take ownership of a pipeline schedule.
The field was deprecated in https://gitlab.com/gitlab-org/gitlab/-/merge_requests/100132.
### Breaking Change
<!--Does this MR contain a breaking change? If yes:
- Add the ~"breaking change" label to this issue.
- Add instructions for how users can update their workflow.-->
### Affected Customers
Who is affected by this deprecation: GitLab.com users, Self-managed users, or Dedicated users? (choose all that apply)
* [x] GitLab.com
* [x] Self-managed
* [x] Dedicated
What pricing tiers are impacted?
* [x] GitLab Free
* [x] GitLab Premium
* [x] GitLab Ultimate
\[ \] Internal note outlining details of customer impact has been created
### Deprecation Milestone
This deprecation will be announced in milestone:`15.9` _If this deprecation has already been announced, include information about when the initial announcement went out and what follow-up announcements are scheduled._
https://docs.gitlab.com/ee/api/graphql/reference/index.html#pipelineschedulepermissions
### Planned Removal Milestone
The feature / functionality will be removed in milestone: `18.0`
### Checklists
**Labels**
- [x] This issue is labeled ~deprecation, and with the relevant `~devops::`, `~group::`, and `~Category:` labels.
- [x] This issue is labeled ~"breaking change" if the removal of the deprecated item will be a [breaking change](https://about.gitlab.com/handbook/product/gitlab-the-product/#examples-of-breaking-changes).
**Timeline**
Please add links to the relevant merge requests.
- [ ] As soon as possible, but no later than the third milestone preceding the major release (for example, given the following release schedule: `14.8, 14.9, 14.10, 15.0` – `14.8` is the third milestone preceding the major release):
- [ ] A [deprecation announcement entry](https://about.gitlab.com/handbook/marketing/blog/release-posts/#creating-a-deprecation-announcement) has been created so the deprecation will appear in release posts and on the [general deprecation page](https://docs.gitlab.com/ee/update/deprecations).
- [x] Documentation has been updated to mark the feature as [deprecated](https://docs.gitlab.com/ee/development/documentation/versions.html#deprecations-and-removals).
- [ ] On or before the major milestone: A [removal entry](https://about.gitlab.com/handbook/marketing/blog/release-posts/#removals) has been created so the removal will appear on the [removals by milestones](https://docs.gitlab.com/ee/update/removals) page and be announced in the release post.
- [ ] On the major milestone:
- [ ] The deprecated item has been removed.
- [ ] If the removal of the deprecated item is a [breaking change](https://about.gitlab.com/handbook/product/gitlab-the-product/#examples-of-breaking-changes), the merge request is labeled ~"breaking change".
**Mentions**
- [ ] Your stage's stable counterparts have been `@mentioned` on this issue. For example, Customer Support, Customer Success (Technical Account Manager), Product Marketing Manager.
- To see who the stable counterparts are for a product team visit [product categories](https://about.gitlab.com/handbook/product/categories/)
- If there is no stable counterpart listed for Sales/CS please mention `@timtams`
- If there is no stable counterpart listed for Support please mention `@gitlab-com/support/managers`
- If there is no stable counterpart listed for Marketing please mention `@cfoster3`
- [ ] Your GPM has been `@mentioned` so that they are aware of planned deprecations. The goal is to have reviews happen at least two releases before the final removal of the feature or introduction of a breaking change.
### Checklists
#### Timeline
#### Rollout Plan
* [ ] DRI Engineers: `@engineer(s)`
* DRI Engineering Manager: @carolinesimpson
* [ ] Describe rollout plans on GitLab.com
* [ ] \_Link to \_[_a feature flag rollout issue_](https://gitlab.com/gitlab-org/gitlab/-/blob/master/.gitlab/issue_templates/Feature%20Flag%20Roll%20Out.md) that covers:
* [ ] Expected release date on GitLab.com and GitLab version
* [ ] Rollout timelines, such as a percentage rollout on GitLab.com
* [ ] Creation of any clean-up issues, such as code removal
* [ ] Determine how to migrate users still using the existing functionality
* [ ] Document ways to migrate with the tooling available
* [ ] Automate any users who have not yet migrated, but ensure it's a two-way door decision
#### Communication Plan
* DRI Product Manager: @rutshah
An internal slack post and a release post are not sufficient notification for our customers or internal stakeholders. Plan to communicate proactively and directly with affected customers and the internal stakeholders supporting them.
Internal Communication Plan
* [ ] Create an internal note in the comment thread of this issue with a comprehensive narrative of customer impacts, with the intended audience of internal stakeholders who directly interact with customers.
* Consider: what will the CSM / AE / SA teams need to tell their customers? What will they want to know about customer sentiment and impact?
* If customers must take an action, include in this internal note the following information: what action is needed, the steps they can take to complete it, the due date for that action, and the consequences of not completing the action in time.
* [ ] Internal announcement plan (timeline for notifications, audience, channels, etc)
* [ ] Support and enablement plan
* Support readiness: Document how the support team should handle tickets related to this deprecation / breaking change.
* Customer Success readiness: Ensure the CS team knows how to bring questions or concerns from clients to the right internal team members.
External Communication Plan
* [ ] Customer announcement plan (timeline for notifications, audience, channels, etc)
* [ ] Ensure you have approvals from legal and corp comms for any communication being sent directly to customers.
* [ ] As soon as possible, but no later than the third milestone preceding the major release, ensure that the following are complete (for example, given the following release schedule: `17.8, 17.9, 17.10, 17.11, 18.0` – `17.9` is the third milestone preceding the major release).
* [x] A [deprecation announcement entry](https://about.gitlab.com/handbook/marketing/blog/release-posts/#creating-the-announcement) has been created so the deprecation will appear in release posts and on the [general deprecation page](https://docs.gitlab.com/ee/update/deprecations). _Add link to the relevant merge request._
* [x] Documentation has been updated to mark the feature as [deprecated](https://docs.gitlab.com/ee/development/documentation/versions.html#deprecations-and-removals). _Add link to the relevant merge request._
* [ ] On the major milestone:
* [ ] The deprecated item has been removed. _Add link to the relevant merge request._
* [ ] If the removal of the deprecated item is a [breaking change](https://docs.gitlab.com/ee/update/terminology.html#breaking-change), the merge request is labeled ~"breaking change".
* [ ] Document the migration plan for users, clearly outlining the actions they need to take to mitigate the impact of the breaking change.
* [ ] Add link
#### Development
* [ ] DRI Engineers: `@engineer(s)`
* DRI Engineering Manager: @carolinesimpson
* [ ] Measure usage of the impacted product feature
* [ ] Evaluate metrics across **GitLab.com, Self-Managed, Dedicated**
* [ ] _add issue link_
* [ ] _list any metrics and/or dashboards_
* [ ] Create tooling for customers to manually migrate their data or workflows
* [ ] _add issue link_
* [ ] Build mechanism for users to manually enable the breaking change ahead of time
* [ ] _add issue link_
* [ ] Automate the migration for those who do not take any manual steps (ensure the automation can be reverted)
* [ ] _add issue link_
* [ ] Develop rollout plan of breaking change on GitLab.com
* [ ] _add feature flag rollout issue_
* [ ] Dogfood the changes on GitLab.com or a Self-Managed test instance
* [ ] _add issue link_
* [ ] (Optional) Create UI controls for instance admins to disable the breaking change, providing flexibility to Self-Managed / Dedicated customers. Optional as this depends on the breaking change.
* [ ] _add issue link_
### Links
<!--Add links to any relevant documentation or code that will provide additional details or clarity regarding the planned change.
This issue is the main SSOT for the deprecations and removals process. Be sure to link all
issues and MRs related to this deprecation/removal to this issue. This can include removal
issues that were created ahead of time, and the MRs doing the actual deprecation/removal work.-->
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