Fix notify_conflict? raising exception due to absent branches

Closes #48653

See merge request gitlab-org/gitlab-ce!20280

Add note for variable usage in singular

See merge request gitlab-org/gitlab-ce!20286

Remove outdated comment from emoji_filter.rb

See merge request gitlab-org/gitlab-ce!20306

repository.can_be_merged? can raise error if diff_head_sha or
target_branch are absent, therefore check those explicitly.

Improve performance of User.without_projects scope

Closes #48577

See merge request gitlab-org/gitlab-ce!20264

Update installation and update guides for 11.1

See merge request gitlab-org/gitlab-ce!20299

Resolve "Milestone page list redesign"

Closes #39543

See merge request gitlab-org/gitlab-ce!19832

Merge branch '42677-cancel-automatic-merge-button-gets-a-bigger-height-than-it-should-when-content-overflows' into 'master'

Resolve "Cancel automatic merge button gets a bigger height than it should when content overflows"

Closes #42677

See merge request gitlab-org/gitlab-ce!20193

Update digital ocean s3 docs

Closes #42510

See merge request gitlab-org/gitlab-ce!20198

Add border to "other" label items

See merge request gitlab-org/gitlab-ce!20250

Resolve "Import with Milestones Failing"

Closes #43270 and #47626

See merge request gitlab-org/gitlab-ce!19961

Use root ref instead of HEAD to find latest repository commit

Closes gitlab-ee#5864

See merge request gitlab-org/gitlab-ce!20258

Improve documentation of how to build Docker Images with GitLab CI

See merge request gitlab-org/gitlab-ce!20254

Add aws_signature_version to object storage docs

Closes #48622

See merge request gitlab-org/gitlab-ce!20257

Cancel ExclusiveLease upon completion in ProjectCacheWorker

Closes #44726

See merge request gitlab-org/gitlab-ce!20103

Resolve "404 when trying to create a new issue from the group"

Closes #47462

See merge request gitlab-org/gitlab-ce!19869

Expire correct method caches after HEAD changed

Closes #44725

See merge request gitlab-org/gitlab-ce!20102

Replaces date.format.js in vendor with NPM package

See merge request gitlab-org/gitlab-ce!20195

Document that DIRECTORY environment variable in backups only applies to remote storage

Closes #38949

See merge request gitlab-org/gitlab-ce!20230

Add locked state to merge request API

See merge request gitlab-org/gitlab-ce!20186

update to support latest bcrypt. resolves #48149

Closes #48149

See merge request gitlab-org/gitlab-ce!20260

i18n: externalize strings from 'app/views/projects/settings'

See merge request gitlab-org/gitlab-ce!19821

Update ee_features.md to fix link

See merge request gitlab-org/gitlab-ce!20283

Signed-off-by: Tao Wang <twang2218@gmail.com>

Performance Improvements to Vue MR page

Closes #48492

See merge request gitlab-org/gitlab-ce!20246

Avoiding a count variable allows more natural translation in some languages.

EE/Geo information paritals not rendered on dashboard

See merge request gitlab-org/gitlab-ce!20276

Update requirements.md to make 8GB the minimum instance size

See merge request gitlab-org/gitlab-ce!20133

Resolve "Merge request collapse icon is tiny"

Closes #48495

See merge request gitlab-org/gitlab-ce!20267