Do not override previously defined before_script

David Dieulivolrequested to merge
ddieulivol-fix_review_checks_jobs into master

What does this MR do and why?

!96583 (merged) broke the review-gcp-quotas-check jobs (see https://gitlab.com/gitlab-org/gitlab/-/jobs/3389007889 for an example).

The before_script for those jobs was overridden, and the gcloud/kubectl setup wasn't done anymore.

This MR ensures that the different before_script are all included.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

Merge request reports