Resolve "First request after GDK server started is slow"

Closes #38930

See merge request gitlab-org/gitlab-ce!16153

Fixed abuse reports link url

See merge request gitlab-org/gitlab-ce!16068

Bumped mysql2 gem version from 0.4.5 to 0.4.10.

See merge request gitlab-org/gitlab-ce!16034

Resolve "Webpack Roadmap"

Closes #38869

See merge request gitlab-org/gitlab-ce!16076

Bump Sidekiq version to 5.0.5

See merge request gitlab-org/gitlab-ce!16151

Unmark Gitaly features as OPT_OUT until the gRPC proxy issue is fixed

Closes #38333

See merge request gitlab-org/gitlab-ce!16155

doc/plantuml.md: use html tags so code fence example would work

[ci skip]

See merge request gitlab-org/gitlab-ce!16026

show None when issue is in closed list and no labels assigned

Closes #40975

See merge request gitlab-org/gitlab-ce!15976

This would make the application considered ready much slower,
but when it's ready, then it's really ready. Before this change,
it claims to be ready, but it's annoyingly slow for the first
request with GDK. It's 100% 502 for me, for the first request.

This shouldn't really affect production or so, because if it's
really ready, it should be blazingly fast, and it should not
slow things down too much.

The culprit here is probably `ActionController::Base.helpers.asset_path`
but this could make sure that anything else would load first, too.

[ci skip]

Table flip quick action docs

See merge request gitlab-org/gitlab-ce!15820

Minor changes: https://github.com/mperham/sidekiq/blob/master/Changes.md

Fix when branch creation fails don't post system note

Closes #24347

See merge request gitlab-org/gitlab-ce!16142

Fix feature flags for Gitaly's RemoteService RPCs

See merge request gitlab-org/gitlab-ce!16150

Humanize the units of "Showing last X KiB of log" in job trace

Closes #38613

See merge request gitlab-org/gitlab-ce!16147

Closes #38613

Fix migration for removing orphaned issues.moved_to_id values in MySQL and PostgreSQL

Closes #41498

See merge request gitlab-org/gitlab-ce!16141

Fix Gitlab::Access.values to Gitlab::Access.sym_options at 06_teams on development db fixtures

See merge request gitlab-org/gitlab-ce!16144

[ci skip]

Use Concurrent::AtomicReference instead AtomicFixnum

Closes #41448

See merge request gitlab-org/gitlab-ce!16138

According to https://dev.mysql.com/doc/refman/5.7/en/update.html,
"You cannot update a table and select from the same table in a subquery."
Attempting to do so results in the error:

```
Mysql2::Error: Table 'issues' is specified twice, both as a target for 'UPDATE' and as a separate source for data
```

Instead, we can use a LEFT JOIN on the same table to make MySQL do the right
thing.

Closes #41498

Closes #24347

Fix Error 500s with anonymous clones for a project that has moved

Closes #41457

See merge request gitlab-org/gitlab-ce!16128

Gracefully handle garbled URIs in Markdown

Closes #41442

See merge request gitlab-org/gitlab-ce!16123

Closes #41457

Update code_climate recommended usage.

See merge request gitlab-org/gitlab-ce!16101