docs: update ci-variables with latest process
This MR updates the process for updating CI Variables. It makes it official that CI Variables updates don't need a review.
I merged the last few MRs that update CI Variables without a review:
The changes are generated with a script and trivial (the script parses markdown documentation table and transforms it into a JSON file). These changes don't change application logic and are tested with unit tests.
I didn't want someone switching their context for trivial changes.