Small banner to show the user why their pipeline was skipped

Contains a large list of files we expect to find for an Auto-DevOps
project.

- Adds UI to configure in group and project settings
- Removes notification configuration for users when
disabled at group or project level

Migrate legacy uploads rake tasks

See merge request gitlab-org/gitlab-ce!29409

Fix starrers counts after searching

See merge request gitlab-org/gitlab-ce!31823

Look up upstream commits once before queuing ProcessCommitWorkers

Closes #65464

See merge request gitlab-org/gitlab-ce!31871

Previously `ProjectCacheWorker` would be scheduled once per ref, which
would generate unnecessary I/O and load on Sidekiq, especially if many
tags or branches were pushed at once. `ProjectCacheWorker` would expire
three items:

1. Repository size: This only needs to be updated once per push.
2. Commit count: This only needs to be updated if the default branch
   is updated.
3. Project method caches: This only needs to be updated if the default
   branch changes, but only if certain files change (e.g. README,
   CHANGELOG, etc.).

Because the third item requires looking at the actual changes in the
commit deltas, we schedule one `ProjectCacheWorker` to handle the first
two cases, and schedule a separate `ProjectCacheWorker` for the third
case if it is needed. As a result, this brings down the number of
`ProjectCacheWorker` jobs from N to 2.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/52046

Instead of checking if a commit already exists in the upstream project
in its ProcessCommitWorker and bailing out if it does, we check the
existence of all commits in bulk in Git::BranchHooksService, so that we
can skip scheduling ProcessCommitWorker jobs for those commits
that already exist upstream entirely.

This removes the group_overview_security_dashboard feature flag

Adds a clipboard button to the metrics dashboard, that allows
copying a link to an individual chart.