Update Auto DevOps' auto-deploy-image to v2.12.0

This adds several new features and bugfixes to Auto Deploy. See
https://gitlab.com/gitlab-org/cluster-integration/auto-deploy-image/-/compare/v2.6.0...v2.12.0
for details.

Changelog: changed

doc/topics/autodevops/customize.md

@@ -383,6 +383,7 @@ applications.
 | `AUTO_DEVOPS_CHART_REPOSITORY_NAME`     | From GitLab 11.11, used to set the name of the Helm repository. Defaults to `gitlab`. |
 | `AUTO_DEVOPS_CHART_REPOSITORY_USERNAME` | From GitLab 11.11, used to set a username to connect to the Helm repository. Defaults to no credentials. Also set `AUTO_DEVOPS_CHART_REPOSITORY_PASSWORD`. |
 | `AUTO_DEVOPS_CHART_REPOSITORY_PASSWORD` | From GitLab 11.11, used to set a password to connect to the Helm repository. Defaults to no credentials. Also set `AUTO_DEVOPS_CHART_REPOSITORY_USERNAME`. |
+| `AUTO_DEVOPS_CHART_REPOSITORY_PASS_CREDENTIALS` | From GitLab 14.2, set to a non-empty value to enable forwarding of the Helm repository credentials to the chart server when the chart artifacts are on a different host than repository. |
 | `AUTO_DEVOPS_DEPLOY_DEBUG`              | From GitLab 13.1, if this variable is present, Helm outputs debug logs. |
 | `AUTO_DEVOPS_ALLOW_TO_FORCE_DEPLOY_V<N>` | From [auto-deploy-image](https://gitlab.com/gitlab-org/cluster-integration/auto-deploy-image) v1.0.0, if this variable is present, a new major version of chart is forcibly deployed. For more information, see [Ignore warnings and continue deploying](upgrading_auto_deploy_dependencies.md#ignore-warnings-and-continue-deploying). |
 | `BUILDPACK_URL`                         | Buildpack's full URL. [Must point to a URL supported by Pack or Herokuish](#custom-buildpacks). |

lib/gitlab/ci/templates/Jobs/DAST-Default-Branch-Deploy.gitlab-ci.yml

 .dast-auto-deploy:
-  image: "registry.gitlab.com/gitlab-org/cluster-integration/auto-deploy-image:v2.6.0"
+  image: "registry.gitlab.com/gitlab-org/cluster-integration/auto-deploy-image:v2.12.0"
 
 dast_environment_deploy:
   extends: .dast-auto-deploy

lib/gitlab/ci/templates/Jobs/Deploy.gitlab-ci.yml

 .auto-deploy:
-  image: "registry.gitlab.com/gitlab-org/cluster-integration/auto-deploy-image:v2.6.0"
+  image: "registry.gitlab.com/gitlab-org/cluster-integration/auto-deploy-image:v2.12.0"
   dependencies: []
 
 review: