There's no need to add a redundant message to the errors if the
model is invalid. This cleans up the message as well for the importer.

Importing a project from GitHub for a project namespace that already exists
would show an unhelpful error, "An error occurred while importing project."
We now add the base message from Projects::CreateService when this fails.

Closes #47365

Merge branch 'blackst0ne-rails5-fix-url_for-in-app-views-admin-runners-index-html-haml' into 'master'

Resolve "[Rails5] Fix params in app/views/admin/runners/index.html.haml"

Closes #47377

See merge request gitlab-org/gitlab-ce!19461

Combine multiple `it` blocks to improve Markdown feature spec times

Closes #47348

See merge request gitlab-org/gitlab-ce!19447

Backport of "Extract EE specific files/lines for app/controllers/groups"

See merge request gitlab-org/gitlab-ce!19343

Add registry debug server docs

See merge request gitlab-org/gitlab-ce!19457

Fix invisible rows on importer status

Closes #47363

See merge request gitlab-org/gitlab-ce!19458

Fix card header text color

Closes #47352

See merge request gitlab-org/gitlab-ce!19451

Fix project settings > merge request settings spacing

Closes #46718

See merge request gitlab-org/gitlab-ce!19444

Fix MR tabs bottom border

Closes #46764

See merge request gitlab-org/gitlab-ce!19446

Reject GPG keys that have e-mail or names with non-valid UTF-8 encodings

Closes #47280

See merge request gitlab-org/gitlab-ce!19455

Resolve "Performance bar modal is hard to read"

Closes #47049

See merge request gitlab-org/gitlab-ce!19334

These were causing 500 Errors when accessing GPG keys for some users.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/47280

Fix repository archive generation when hashed storage is enabled

Closes #45702

See merge request gitlab-org/gitlab-ce!19441

Fix transfer project namespace field

Closes #47345

See merge request gitlab-org/gitlab-ce!19445

Fix header styles

Closes #46704 and #46697

See merge request gitlab-org/gitlab-ce!19443

fix attach button cursor

Closes #46713

See merge request gitlab-org/gitlab-ce!19401

Update _destroy.haml

See merge request gitlab-org/gitlab-ce!19355

The setup of each spec is too expensive to perform as many times as we
were doing it. Reduced duration from 255 seconds to 43.

Revert "Merge branch 'jivl-add-top-margin-related-merge-requests' into 'master'"

See merge request gitlab-org/gitlab-ce!19442

This reverts merge request !19379

Fix group activity border to extend under RSS link

See merge request gitlab-org/gitlab-ce!19362

Add top margin to the related merge requests section

Closes #46697

See merge request gitlab-org/gitlab-ce!19379

Improve pipeline index action performance by using persisted stages

Closes #43132

See merge request gitlab-org/gitlab-ce!19063

Resolve "Keyboard shortcuts modal is broken"

Closes #47053

See merge request gitlab-org/gitlab-ce!19308

use HTTPS in the example GitLab Page URL

See merge request gitlab-org/gitlab-ce!19403