Let us set staging job run params

This lets us run the staging scenario with options (e.g., run only one test, or a specific release image, as needed to test https://gitlab.com/gitlab-org/gitlab/-/merge_requests/36236 against staging before merging).

Also authenticates with the container registry via a CI job token only when triggered by pipeline. Otherwise it will use a username and access token so that the job can be run in MRs or as a standalone pipeline.

Finally, it masks tokens in logs (including exceptions). Allows for masking any string in docker commands.