Modify k8s-workloads/gitlab-com to enable auto-deploy

Modify the project k8s-workloads/gitlab-com to be able to achieve the following:

• Accept a triggered job that contains the following information:
  • gitlab-com/gl-infra/k8s-workloads/gitlab-com!172 (merged)
  • gitlab-com/gl-infra/k8s-workloads/gitlab-com!176 (merged)
  • gitlab-com/gl-infra/k8s-workloads/gitlab-com!188 (merged)
  • gitlab-com/gl-infra/k8s-workloads/gitlab-com!189 (merged)
  • input for desired Image Version to be deployed
  • DRY_RUN for dry-runs
  • AUTO_DEPLOY to ensure that only specifically chosen jobs run
• Add ability to query the existing installation for running Chart Version
  • gitlab-com/gl-infra/k8s-workloads/common!54 (merged)
  • gitlab-com/gl-infra/k8s-workloads/common!55 (merged)
• Add ability to set the Image Version during deploy job
  • gitlab-com/gl-infra/k8s-workloads/gitlab-com!183 (merged)
  • gitlab-com/gl-infra/k8s-workloads/gitlab-com!184 (merged)
  • gitlab-com/gl-infra/k8s-workloads/gitlab-com!170 (merged)
  • If passed in via the environment - must be an auto-deploy, utilize this version
  • If missing from environment - grab version from cluster - ensure this is populated for helmfile to prevent upgrades or downgrades during deployments
• Document
  • gitlab-org/release/docs!212 (merged)