Change project FK migration to skip existing FKs

Closes #35243

See merge request !13235

Add icons to project sidebar

Closes #34027 and #35877

See merge request !13204

Uniquify reserved word usernames on OAuth user creation

See merge request !13244

Synchronous zanata community contribution translation

Closes #35003

See merge request !13242

Show auto-generated avatars in Groups dashboard tree for Groups without avatars

See merge request !13188

Make Delete Merged Branches handle wildcard protected branches correctly

Closes #35592

See merge request !13251

Update milestone docs CE

See merge request !13233

The "Delete Merged Branches" button should filter out protected
branches matching the wildcard patterns.

Closes gitlab-org/gitlab-ce#35592.

This changes the migration ProjectForeignKeysWithCascadingDeletes so
that it does not add already existing foreign keys and indexes, making
it easier to re-run the migration.

Expose target_iid in Events API

See merge request !13247

Extending API for protected branches

See merge request !12756

Add rugged_is_ancestor method

See merge request !13232

Fix Issue board when using Ruby 2.4

Closes #35769

See merge request !13220

Make the 'issuables list meta-data' shared example less dangerous

See merge request !13236

Ensure all project factories use `:repository` trait or `:empty_project`

See merge request !13238

Add filtered search to group issue dashboard

Closes #33575

See merge request !13167

Remove jQuery cropper plugin from vendors directory

See merge request !13239

Add kube_namespace and standardize common variables for additional metrics queries

See merge request !13169

Fix encoding error for WebHook logging

Closes #35815

See merge request !13230

Make Markdown autocomplete dropdowns style consistent

See merge request !13127

Derive project path from import URL

Closes #27341

See merge request !13131

Docs: update articles list

Closes #35800

See merge request !13229