Replace Code Quality job definition with a vendored template

Problem to solve

Job definition for ~"code quality" is frozen, and can't be easily updated without creating breaking changes.

Further details

With https://gitlab.com/gitlab-org/gitlab-ce/issues/53445, we'll be able to ship a template embedded with each version of GitLab. The template can be updated from one version to another, without impacting our users.

Proposal

What does success look like, and how can we measure that?

The new official job definition is a single inclusion instruction:

include:
  template: Code-Quality.gitlab-ci.yml

Execution

• Add the Code-Quality.gitlab-ci.yml with the contents from the example to the templates dir under Verify subdir
• Test in the development environment on a test project
• Update the ~Documentation
  • docs page, see https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/9875
  • Update the code quality project to make it clear how updating the template will work in the future.

Reference

For reference for previous similar issues, see what ~Secure did with SAST, DAST, container scanning as well as ~Configure's plans around Composable Auto DevOps