Allow fork MRs to create a pipeline in a parent project if the pipeline triggerer has permission in the parent
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### Problem to solve
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As a developer that has permissions for both forked and parent project, I want to be able to allow fork MRs to create a pipeline in a parent project and trigger the parent pipeline without the need of another manual step (https://gitlab.com/gitlab-org/gitlab/-/issues/217451)
### Intended users
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* [Sasha (Software Developer)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#sasha-software-developer)
### User experience goal
<!-- What is the single user experience workflow this problem addresses?
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### Proposal
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**1. Allow fork MRs to create a pipeline in a parent project if the pipeline triggerer has permission in the parent (i.e. a Developer role or above)**
* This feature is useful for users who depend on private-fork workflow. The parent project can ensure that pipelines created by fork projects are always evaluated in the same condition with the parent's CI resource/setting.
* If the user in a fork project is not member of a parent or doesn't have a sufficient permission to create a pipeline (e.g. Reporter role), the pipeline location falls back to a fork project.
* This feature is disabled by default. You need to enable a checkbox in the project setting in a parent project. (Something similar to https://gitlab.com/gitlab-org/gitlab/-/issues/11934#ux-proposal)
* For giving a permission to a fork user, a parent project maintainer (or above) has to add the user to the project *manually*. This might be cumbersome if there are many fork users.
* This feature is *not* useful if a parent project cannot fully-trust fork users, as giving a membership is equal to grant an access to majority of resources in parent, that could result in abuse. For example, GitLab's main repository `gitlab.com/gitlab-org` would never enable it (i.e. no dogfooding).
* The weight of development is medium.
* This feature would be able to be extended to have a resource control on top of membership control. This weight of development would be XL or above.
### Further details
<!-- Include use cases, benefits, goals, or any other details that will help us understand the problem better. -->
### Permissions and Security
<!-- What permissions are required to perform the described actions? Are they consistent with the existing permissions as documented for users, groups, and projects as appropriate? Is the proposed behavior consistent between the UI, API, and other access methods (e.g. email replies)?-->
We need to make sure that this option is available for users who have developer Role or up in the parent project.
* Users who are members of the parent project but are not developers and up should not go through this workflow.
* Users who are not members of the parent project at all should not go through this workflow but rather https://gitlab.com/gitlab-org/gitlab/-/issues/217559
### Documentation
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* If this feature requires changing permissions, update the permissions document. See https://docs.gitlab.com/ee/user/permissions.html -->
### Availability & Testing
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What risks does this change pose to our availability? How might it affect the quality of the product? What additional test coverage or changes to tests will be needed? Will it require cross-browser testing?
Please list the test areas (unit, integration and end-to-end) that needs to be added or updated to ensure that this feature will work as intended. Please use the list below as guidance.
* Unit test changes
* Integration test changes
* End-to-end test change
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### What does success look like, and how can we measure that?
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### What is the type of buyer?
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### Is this a cross-stage feature?
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### Links / references
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