The SanitizationFilter was running before the WikiFilter. Since
WikiFilter can modify links, we could see links that _should_ be stopped
by SanatizationFilter being rendered on the page. I (kerrizor) had
previously addressed the bug in: https://gitlab.com/gitlab-org/gitlab-ee/commit/7bc971915bbeadb950bb0e1f13510bf3038229a4
However, an additional exploit was discovered after that was merged.
Working through the issue, we couldn't simply shuffle the order of
filters, due to some implicit assumptions about the order of filters, so
instead we've extracted the logic that sanitizes a Nokogiri-generated
Node object, and applied it to the WikiLinkFilter as well.

On moving filters around:
Once we start moving around filters, we get cascading failures; fix one,
another one crops up. Many of the existing filters in the WikiPipeline
chain seem to assume that other filters have already done their work,
and thus operate on a "transform anything that's left" basis;
WikiFilter, for instance, assumes any link it finds in the markdown
should be prepended with the wiki_base_path.. but if it does that, it
also turns `href="@user"` into `href="/path/to/wiki/@user"`, which the
UserReferenceFilter doesn't see as a user reference it needs to
transform into a user profile link. This is true for all the reference
filters in the WikiPipeline.

[ci skip]

Support object storage at FileMover class

See merge request gitlab/gitlabhq!3196

[ci skip]

Ability to write a note in a private snippet

See merge request gitlab/gitlabhq!3141

Prevent Billion Laughs attack

See merge request gitlab/gitlabhq!3144

Guests can know whether merge request template name exists or not

See merge request gitlab/gitlabhq!3149

Fix MR head pipeline leak

See merge request gitlab/gitlabhq!3155

Fix DOS when rendering issue/MR comments

See merge request gitlab/gitlabhq!3158

Persist tmp snippet uploads at users

See merge request gitlab/gitlabhq!3165

Expose merge requests count based on user access

See merge request gitlab/gitlabhq!3168

Fix type authorizations in GraphQL

See merge request gitlab/gitlabhq!3173

Fix color validation regex causing DoS

See merge request gitlab/gitlabhq!3177

Disable Rails SQL query cache when applying service templates

See merge request gitlab/gitlabhq!3180

[ci skip]

Prepare 11.11.4 release

See merge request gitlab-org/gitlab-ce!30069

Master i18n 11.11

See merge request gitlab-org/gitlab-ce!30083

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