[ci skip] Disable submit button when submitting a note or if the note is empty while editing or adding a reply to a discussion

* master: (76 commits)
  Add code review guidelines related to Build [CI skip].
  Make time span dropdown style on cycle analytics page consistent
  Add 204. Remove duplicated method.
  Make sure we didn't commit conflicts
  Fix bug in blob test
  Always fetch branches before finding the merge base, otherwise we could find an outdated merge base
  Fixes dropdown margin in sidebar
  Docs add blog articles
  Inline script cleanup globals and easy
  Add option to use CommitLanguages RPC
  CI fixes for gitaly-ruby
  fix
  Allow logged in users to read user list under public restriction
  Small refactor in LegacyNamespace and moved back send_update_instructions
  Rename ensure_dir_exist -> ensure_storage_path_exist
  Added some extra TODOs for the Legacy Storage refactor
  Make disk_path keyword argument and optional
  Rename more path_with_namespace -> full_path or disk_path
  Rename path_with_namespace -> disk_path when dealing with the filesystem
  Rename many path_with_namespace -> full_path
  ...

Resolve "Remove `events` from `notification_settings`"

Closes #33620

See merge request !13152

Bump rubocop to 0.49.1 and rubocop-rspec to 1.15.1

Closes #34869

See merge request !12741

Add code review guidelines related to Build [CI skip].

See merge request !13223

Fix "API specs and linting failing on master"

Closes #35825

See merge request !13227

Make time span dropdown style on cycle analytics page consistent

See merge request !13183

Always fetch branches before finding the merge base, otherwise we could find an outdated merge base

See merge request !13226

Fix bug in blob test

See merge request !13224

[CE] Added Legacy Storage format

See merge request !13149

Make sure we didn't commit conflicts

Closes #35627

See merge request !13141

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

Fixes dropdown margin in sidebar

Closes #35690

See merge request !13205

Add option to use Gitaly CommitLanguages RPC

See merge request !13084

Remove `services: true` from spec/services/ci/pipeline_trigger_service_spec.rb

See merge request !13219

Fix deletion of deploy keys linked to other projects

Closes #35630

See merge request !13162

Remove unused Gitlab::Diff code

See merge request !13195

Invalid variable

See merge request !13214

Fix username typo (jonh to John)

See merge request !13210

Uses jQuery to scroll since setting document.body.scrollTop does not work in firefox

Closes #34492

See merge request !13203

Extend API: Group Secret Variable

Closes #34519

See merge request !12936

Docs add blog articles

Closes #34633

See merge request !13209

Inline script cleanup globals and easy

See merge request !12969