Merge branch 'security-ruby-graphql' into 'master'

See merge request gitlab-org/security/gitlab!4832

Changelog: security

Merge branch 'security-dblessing-ruby-saml' into 'master'

See merge request gitlab-org/security/gitlab!4819

Changelog: security

The usage has been removed a while ago, let's remove the gem itself
from the Gemfile

The version we've been using - v5.1.0 - is more than four years out of
date. It doesn't include matchers for the use of
ActiveRecord::Encryption, which is important for us to have as we
migrate to ActiveRecord::Encryption from the attr_encrypted gem.

The version constraint on oj seems very strict, so let's relax it a
little bit, so that the version can be bumped independently in the
main lockfile.

- Fix breaking changes introduced by 0.28.0

The version constraint on json seems very strict, so let's relax it a
little bit, so that the version can be bumped independently in the
main lockfile.

Changelog: fixed

Following the first few steps of "Verify upcoming release
of gitlab-styles" from [Checklist][1].

Specifically, ran:
```console
$ bundle install && \
  bundle exec bundler-checksum init && \
  bundle install --gemfile Gemfile.next && \
  cp Gemfile.lock Gemfile.next.lock && \
  BUNDLE_GEMFILE=Gemfile.next bundle lock && \
  BUNDLE_GEMFILE=Gemfile.next bundle exec bundler-checksum init && \
  bundle exec rubocop
...
41153 files inspected, 127 offenses detected, 124 offenses autocorrectable
```

[1]: https://gitlab.com/gitlab-org/gitlab/-/blob/master/.gitlab/merge_request_templates/New%20Version%20of%20gitlab-styles.md#checklist