Add Merge Requests support for Jira Development Panel

Closes #2646

See merge request gitlab-org/gitlab-ee!5534

Report git status whenever ee-specific-lines-check failed to rebase cleanly

See merge request gitlab-org/gitlab-ee!5594

Repository verification on Geo secondary

Closes #5564 and #4746

See merge request gitlab-org/gitlab-ee!5550

Update item titles and add help text in Geo nodes admin dashboard

Closes #5146

See merge request gitlab-org/gitlab-ee!5306

This way it would be much easier to debug

Closes gitlab-org/gitlab-ee#5564

For easier overriding methods.

Pick the changes from gitlab-org/gitlab-ce!18484 into EE.

autocomplete usernames in Epic comments/description

Closes #4084

See merge request gitlab-org/gitlab-ee!5475

[EE] Remove top margin on the terms page with performance bar

See merge request gitlab-org/gitlab-ee!5579

EE port of Update instalation from source guide

See merge request gitlab-org/gitlab-ee!5574

When both the performance bar and the system header are enabled.

Merge branch 'ee-44059-specify-variables-when-executing-a-manual-pipeline-from-the-ui' into 'master'

Ee 44059 specify variables when executing a manual pipeline from the ui

See merge request gitlab-org/gitlab-ee!5413