Add "Archive Label" feature
### Problem to solve
While Label clutter is a real problem and admins have a legitimate need to prune old Labels, deleting a Label can break reporting and delete useful historical associations.
### Intended users
The primary user would be any of the [IT roles](https://about.gitlab.com/handbook/marketing/product-marketing/enterprise-it-roles/) that might be a GitLab administrator, but all of our user personas would be affected by the outcome.
### User experience goal
From the Label List ([example](https://gitlab.com/gitlab-org/gitlab/-/labels)) or Label Edit ([example](https://gitlab.com/groups/gitlab-org/-/labels/13668508/edit)) pages, a user with authority to modify a Label ([related issue](https://gitlab.com/gitlab-org/gitlab/-/issues/216637)) would could Archive a Label.
Archiving a Label would:
* Remove the ability of users to view or assign the Label when creating or editing any issues, MRs, or epics
* Remove the Label from the default Label list view
Archiving a Label would not:
* Delete any associations with Labeled issues, Epics, or MRs
* Disrupt any Insights dashboards or other reporting capabilities.
Longer-term, it would be wonderful to have a toggle that allows users to include archived Labels in their searches.
### Further details
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### Permissions and Security
This does not seems like it would require any reworking of permissions, beyond what would be necessary for the related issue noted above.
### Documentation
Affected pages would include:
* https://docs.gitlab.com/ee/user/project/labels.html
### Availability & Testing
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* Integration test changes
* End-to-end test change
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### What does success look like, and how can we measure that?
The ability to:
* Declutter a Label list by archiving one or more Labels
* Verify that the Label can no longer be added to an issue, MR, or epic
* Verify that an existing report (e.g., an Insights dashboard) referencing the archived Label continues to identify that Label and associated items.
* Verify that the Label can be reactivated and return to its prior state without disrupting any previous associations.
### What is the type of buyer?
I think this could be of benefit to anyone, at any tier, but [Erin](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/buyer-persona/#erin---the-application-development-executive-vp-etc) would probably be the most concerned of the buyer personas.
### Is this a cross-stage feature?
This seems fairly focused on Plan (@gweaver )
### Links / references
issue