+ clean transaction metrics

+ Gemfile.lock file update

+ Cleanup sampler, use latest Prometheus gem

Resolve "Add a `merge_request_diff_id` column to `merge_requests`"

See merge request gitlab-org/gitlab-ce!15035

Refactor responsive table styles to support nested error block

See merge request gitlab-org/gitlab-ce!15145

Incorporate Gitaly's OperationService.UserFFBranch RPC

Closes gitaly#693

See merge request gitlab-org/gitlab-ce!15040

Once we migrate existing MRs to have this column, we will be able to get the
latest diff for a single merge request more efficiently, and (more importantly)
get all latest diffs for a collection of MRs efficiently.

We already had this the other way around (merge_request_diffs.merge_request_id),
but this is needed to gather only the most recent diffs for a set of merge
requests.

Update .nvmrc to v9.0.0 (current stable)

See merge request gitlab-org/gitlab-ce!15149

Convert Icons in CI to SVG Sprite Icons

See merge request gitlab-org/gitlab-ce!14567

Document GitLab pages prerequisite with external HTML artifacts

See merge request gitlab-org/gitlab-ce!15153

Send SIGSTP before SIGTERM to actually give Sidekiq jobs 30s to finish when the memory killer kicks in

See merge request gitlab-org/gitlab-ce!15102

Remove Private Tokens

Closes #38595 and #38447

See merge request gitlab-org/gitlab-ce!14838

Remove an exception from the git user default SSH config check

See merge request gitlab-org/gitlab-ce!15151

Remove useless closeReopenReport specs

Closes gitlab-ee#3890

See merge request gitlab-org/gitlab-ce!15133

Prompted to add this note from
https://gitlab.com/gitlab-org/gitlab-ce/issues/34102#note_45522526

Send SIGSTP before SIGTERM to actually give Sidekiq jobs 30s to finish when the memory killer kicks in

Use `count` expectation on `all` finder for patient specs (address flakey recent searches specs)

Closes #34435

See merge request gitlab-org/gitlab-ce!14961

Clarify the weights that identify issues for beginners

See merge request gitlab-org/gitlab-ce!15138

CE port of code changed for epics

See merge request gitlab-org/gitlab-ce!15144

Measure Gitaly migration sites against original

See merge request gitlab-org/gitlab-ce!15118

Make NamespaceSelect change URL when filtering

Closes #37277

See merge request gitlab-org/gitlab-ce!14888

Geo route whitelisting is too optimistic

Closes gitlab-ee#3274

See merge request gitlab-org/gitlab-ce!15082

Change to new GitLab Runner name

Closes #39636

See merge request gitlab-org/gitlab-ce!15101

Fix webhook recent deliveries elapsed time field

Closes #39704

See merge request gitlab-org/gitlab-ce!15146

Add debugging section to testing_guide/best_practices.md.

See merge request gitlab-org/gitlab-ce!14858

Signed-off-by: Rémy Coutable <remy@rymai.me>

 - Split layout from the styles of the row
 - Move command `.append-` `.prepend-` styles to bottom of source order
    - Actually applies styles over others in more situations which is
      probably what is expected when you add it to an element
    - Also allows us to get rid of some styles that were trying to get
      around this fact

See https://i.imgur.com/IE50PK6.png
Which is used in
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/15064

Design from https://gitlab.com/gitlab-org/gitlab-ce/issues/38464

Fix cancel button not working when uploading a file on the new issue page

Closes #39512

See merge request gitlab-org/gitlab-ce!15137