WIP: Disable docker-in-docker for SAST
What does this MR do?
Related issue: #197205 (closed)
This MR disables docker-in-docker for SAST. We want to move to having docker-in-docker be disabled by default for everyone [citation needed] and this helps us dogfood that initiative.
This will also parallelize the various SAST scans (secrets, eslint, nodejs-scan, brakeman, kubesec), which will speed up SAST as a whole, which is currently the bottleneck job for some pipelines, such as https://gitlab.com/gitlab-org/gitlab/-/jobs/402196624.
Documentation for disabling docker-in-docker: https://docs.gitlab.com/ee/user/application_security/sast/#disabling-docker-in-docker-for-sast