Fix Error 500s creating merge requests with external issue tracker

Closes #43193

See merge request gitlab-org/gitlab-ce!17073

Cleanup new branch/merge request form in issues

Closes #41938

See merge request gitlab-org/gitlab-ce!16854

When JIRA or Redmine were enabled and the branch name did not match the
matching regular expression, the `issue_iid` would be `nil`, preventing
users from creating merge requests.

Closes #43193

Updated katex library

Closes #43032

See merge request gitlab-org/gitlab-ce!15864

Clean new Flash() and stop disabling no-new (eslint) when possible

Closes #42732

See merge request gitlab-org/gitlab-ce!17060

Disable query limiting warnings for now on GitLab.com

See merge request gitlab-org/gitlab-ce!17067

Honour workhorse provided file name

See merge request gitlab-org/gitlab-ce!17059

Fix warning messages for promoting labels and milestones

Closes #42900

See merge request gitlab-org/gitlab-ce!17063

Merge branch 'rd-43185-revert-sanitize-extra-blank-spaces-used-when-uploading-a-ssh-key' into 'master'

Revert "Merge branch 'rd-40552-gitlab-should-check-if-keys-are-valid-before-saving' into 'master'"

See merge request gitlab-org/gitlab-ce!17062

Fixed missing js selector for the realtime pipelines commit component

See merge request gitlab-org/gitlab-ce!17061

Convert groups_select ajax to use axios

See merge request gitlab-org/gitlab-ce!17041

This reverts commit a58f8c32, reversing
changes made to cd5d75c3.

In the attempt to unify file uploading at workhorse level gitlab-org/gitlab-workhorse!230
we moved to a prefix-based tempfile creation in order to avoid upload collisions.

Artifacts and LFS uploads already set original_filename to workhorse provided filename

This commit add the same feature to `Gitlab::Middleware::Multipart`

Make GITLAB_FEATURES in build_spec compatible with EE

Closes #40994

See merge request gitlab-org/gitlab-ce!17023

Create an empty wiki when there is no wiki in the gitlab export bundle

See merge request gitlab-org/gitlab-ce!17010

Fix breadcrumb on labels page for groups

Closes #42909

See merge request gitlab-org/gitlab-ce!17045

Replaced use of $.get with axios.get and updated tests

See merge request gitlab-org/gitlab-ce!16989

Fix issue with Gitlab::CurrentSettings and autoload/spring system

Closes gitlab-ee#4842

See merge request gitlab-org/gitlab-ce!17037

Move IssuableTimeTracker vue component

See merge request gitlab-org/gitlab-ce!16948

Default CI variables to unprotected

Closes #42928

See merge request gitlab-org/gitlab-ce!17039

Update jquery.waitforimages & use npm version

See merge request gitlab-org/gitlab-ce!17004

GitLab QA: Add GITLAB_USER_TYPE to support different login types (e.g. standard, LDAP)

See merge request gitlab-org/gitlab-ce!17048

Resolve "Add tooltip in enviroments names"

Closes #42922

See merge request gitlab-org/gitlab-ce!17029

Rename .scss files to use snake_case

Closes #42908

See merge request gitlab-org/gitlab-ce!17022

API - fix searching in group/project specified by path

Closes #42937

See merge request gitlab-org/gitlab-ce!17033

GITLAB_USERNAME and GITLAB_PASSWORD may be specified for an LDAP login, but QA
scenarios may need to know which type it is in order to log in successfully.

Return a warning string if we try to encode to unsupported encoding

Closes gitlab-development-kit#321

See merge request gitlab-org/gitlab-ce!17038

Remove confirmation_input component

See merge request gitlab-org/gitlab-ce!17046