Add index on ci_runners.contacted_at

Closes #31229

See merge request !10876

Improve Slack docs

See merge request !10927

Merge branch '29181-add-more-tests-for-spec-controllers-projects-builds-controller-spec-rb' into 'master'

Resolve "Add more tests for spec/controllers/projects/builds_controller_spec.rb"

Closes #29181

See merge request !10244

Make markdown tables thinner

Closes #14123

See merge request !10909

Remove top padding on project list row

See merge request !10939

Refactor rich blob viewers and add Code|Rendered switch

Closes #24287

See merge request !10566

Increase line-height in build-header so elements don't overlap

See merge request !10712

Fixed alignment of CI icon in related issues section

Closes #31228

See merge request !10962

Skip validation when creating internal (ghost, service desk) users

See merge request !10949

Run `bundle check` after `bundle install` instead of having a dedicated job for it

Closes #31464

See merge request !10944

improves test settings for chat notification services for empty projects

Closes #31138

See merge request !10886

Make api/v3/deployments_spec to actually tests v3 instead of current API

See merge request !10965