Add vale lint to pipeline
Copies over changes in https://gitlab.com/gitlab-com/content-sites/internal-handbook/-/merge_requests/4900
- Outputs vale results to job log.
- Creates codequality report so that errors and warnings show in diff.
- Adds vale templates to format output for job log, and in json for codequality.
- Updates vale configuration as needed.
- Adds a CI job and script to run vale on changed files.
- Updates codequality parse to account for vale results.
Related to #151 (closed)
Edited by Cynthia "Arty" Ng