Removed `Milestone#is_empty?`

Closes #30056

See merge request !10523

Hide zero counters on header

Closes #30449

See merge request !10506

Update droplab

See merge request !9444

Fix new group button label in GitLab QA specs

See merge request !10529

Send more Gitaly::Repository fields

See merge request !10499

Doc: Search through GitLab

Closes #13251

See merge request !10463

Remove confusing placeholder for JIRA transition_id

Closes #28574

See merge request !10421

Backport permissions and multi-line array to CE

See merge request !10507

FE: Resolve "Performance issues when processing large build traces with Ansi2html"

Closes #27724

See merge request !10336

Add /-/readiness /-/liveness and /-/health_metrics endpoints to track application readiness

Closes #24240

See merge request !10416

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Add auto-cancel for pending pipelines on branch, if they are not HEAD

See merge request !9362

Fix markdown table in API Issues docs

See merge request !10500

Adds polling function to pipelines table

Closes #5983

See merge request !10210

Update Prometheus documentation for 9.1

See merge request !10516

* upstream/master: (58 commits)
  Fix icon name error
  Rewrite system note helper
  Change edit icon
  Leave icon area blank if legacy note; remove diamond icon
  Fix positioning of note icons
  Fix newline errors
  Add remaining system note icons
  Add system notes icon helper; add icons
  Fixed specs Updated JS that was causing the hints to appear & then disappear
  Update tests
  Fix broken spinach test
  Reuse code
  Improve shortcuts code
  Adds ShortcutsDashboardNavigation to globals comment since its a global variable
  Fix shortcut specs
  Reorganize shortcut help menu
  Change todos shortcut to shift
  Change shortcuts
  Switch global shortcuts to shift; reuse key styles from help menu
  Map bindings to lowercase letters; only show key bindings when using keyboard shortcut
  ...

Stop new merge request page tabs updating the URL

Closes #30419

See merge request !10471

Removed `Milestone#is_empty?` because is not used anymore in the codebase

Removes unused code

See merge request !10456