Harden the wiki against missing last_versions

Closes #52527

See merge request gitlab-org/gitlab-ce!22377

Remove prometheus configuration help text

Closes #52782

See merge request gitlab-org/gitlab-ce!22413

Use cached readme blobs where appropriate

Closes #49591

See merge request gitlab-org/gitlab-ce!22325

Fixed bug with the content disposition with wiki attachments

See merge request gitlab-org/gitlab-ce!22220

Round P/S labels up, not down

See merge request gitlab-org/gitlab-ce!22424

GitLab keeps a cache of the rendered HTML for a repository's README as
stored in the HEAD branch. However, it was not used in all
circumstances. In particular, the new blob viewer framework bypassed
this cache entirely.

This MR ensures a ::ReadmeBlob is returned instead of a ::Blob when
asking a repository for an individual blob, if the commit and path
match the readme for HEAD. This makes the cached HTML available to
consumers, including the blob viewer.

The ReadmeBlob is a simple delegator to the Blob, so should be
compatible in all cases. Adding the rendered_markdown method is the
only additional behaviour it contains.

add link to concurrent devops

See merge request gitlab-org/gitlab-ce!22071

Remove gitlab-grit as a transitive dependency of GitLab

Closes #44361

See merge request gitlab-org/gitlab-ce!22373

Currently, we assume a "last_version" always exists for a wiki page.
In production, this is not always true. So, guard uses of it with a
null check.

Extend Create New Merge Request test to also add a label

Closes gitlab-qa#233

See merge request gitlab-org/gitlab-ce!19228

Update environments empty state

See merge request gitlab-org/gitlab-ce!22297

Add Git protocol v2 docs

See merge request gitlab-org/gitlab-ce!22227

[ci skip]

Replace job with group in frontend components to be consistent with backend

See merge request gitlab-org/gitlab-ce!22387

Allow JIRA to login using email and API token

Closes #49936

See merge request gitlab-org/gitlab-ce!21726

Add documentation on using NFS v4.1 and disabling server delegations

See merge request gitlab-org/gitlab-ce!22379

Resolve "Integrate new vue+vuex code base with new API and remove old haml code"

Closes #50904

See merge request gitlab-org/gitlab-ce!22116

Resolve "In web editor, when delete a file, should navigate to enclosing directory"

Closes #37727

See merge request gitlab-org/gitlab-ce!21465

3. enable jasmine/new-line-before-expect

See merge request gitlab-org/gitlab-ce!22234

Prettify all the things (part 8)

See merge request gitlab-org/gitlab-ce!22258

Prettify all the things (part 1)

See merge request gitlab-org/gitlab-ce!22248

Resolve "Share frontend configs between repos"

Closes #49740

See merge request gitlab-org/gitlab-ce!22405

2. enable jasmine/no-promise-without-done-fail

See merge request gitlab-org/gitlab-ce!22231

For more info, see:

* https://gitlab.com/gitlab-org/gitaly/issues/1339
* https://gitlab.com/gitlab-org/gitlab-ce/issues/52017

Fix "ready for review" link

See merge request gitlab-org/gitlab-ce!22393