Remove 'Disable project' button from project view

[janfaracik]

Discussed briefly in the last UX Sig, the 'Disable project' (and 'Add/edit description') button take up a lot of vertical space (roughly 100px) and this forces useful information, such as stage view plugin etc down.

My proposal would be just to remove the 'Disable project' button altogether and instead have users rely on the configure screen to disable projects.

Before

After

Testing done

• Disable button has been removed, still possible to reenable a project from that view however

Proposed changelog entries

• Remove 'Disable project' button from project view

Proposed upgrade guidelines

N/A

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Desired reviewers

@jenkinsci/sig-ux

Before the changes are marked as ready-for-merge:

### Maintainer checklist
- [ ] There are at least two (2) approvals for the pull request and no outstanding requests for change.
- [ ] Conversations in the pull request are over, or it is explicit that a reviewer is not blocking the change.
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[timja]

I never used that button on my own, but wouldn't it make sense to remove it when we move all those actions to the action bar?

This button is also on the configure page so its just duplicated so I think its a special case.

[daniel-beck]

Isn't this a good use case for app-bar buttons?

[janfaracik]

I never used that button on my own, but wouldn't it make sense to remove it when we move all those actions to the action bar?

Isn't this a good use case for app-bar buttons?

I agree with Tim here, this is a duplicated button that isn't very often used for how prominent it is. Demoed an app bar rework for the project page in the latest UX meeting in which it could live, but not sure how useful it would be to have there.

[timja]

/label ready-for-merge

---

This PR is now ready for merge, after ~24 hours, we will merge it if there's no negative feedback.

Thanks!

[basil]

This change breaks org.jenkinsci.plugins.workflow.job.WorkflowJobTest#disabled. Since I have detected the breakage before this change has shipped in a weekly release, and since I do not yet see a PR to adapt workflow-job to this breaking change, I am planning to revert this change before tomorrow's weekly ships to avoid breaking BOM/PCT. We can reintegrate this change in a future weekly once workflow-job has been adequately prepared for this breaking change. If a PR to adapt workflow-job to this breaking change appears before tomorrow's weekly release, then I won't revert this change.