GITLAB_MIRROR_PREFIX variable

Signed-off-by: Dmitriy Safronov <zimniy@cyberbrain.pw>

Auto-DevOps.gitlab-ci.yml

@@ -2,7 +2,7 @@ include:
   - template: Auto-DevOps.gitlab-ci.yml
 
 variables:
-  GITLAB_MIRROR_PREFIX: "${CI_REGISTRY}/gitlab"
+  # Set `GITLAB_MIRROR_PREFIX` variable on the instance/group/project level. Exapmple - GITLAB_MIRROR_PREFIX: "${CI_REGISTRY}/gitlab"
   SECURE_ANALYZERS_PREFIX: "${GITLAB_MIRROR_PREFIX}/security-products"
   CLUSTER_INTEGRATION_PREFIX: "${GITLAB_MIRROR_PREFIX}/cluster-integration"
   CODE_QUALITY_PREFIX: "${GITLAB_MIRROR_PREFIX}/codequality"

README.md

@@ -13,3 +13,5 @@ include:
 ```
 
 ...where `project: 'gitlab/auto-devops'` contains absolute path to this repository from the root of your gitlab instance without leading slash.
+
+Set `GITLAB_MIRROR_PREFIX` variable on the instance/group/project level.