WIP: Flatten further

For https://gitlab.com/gitlab-org/gitlab-ce/issues/29412.

Auto-deploy-kubernetes.yml

-# Explanation on the scripts:
-# https://gitlab.com/gitlab-examples/kubernetes-deploy/blob/master/README.md
-
 ##############################
 # Define some helper functions
 ##############################
@@ -167,11 +164,16 @@
 # Define basic job definitions
 ##############################
-.kubernetes-deploy: &kubernetes-deploy
+.auto_deploy_image: &auto_deploy_image
   image: registry.gitlab.com/gitlab-examples/kubernetes-deploy
   before_script:
     - *common
+# .openshift-deploy: &openshift-deploy
+#   image: registry.gitlab.com/gitlab-examples/openshift-deploy
+#   before_script:
+#     - *common
+
 .build_branches: &build_branches
   stage: build
   script:
@@ -277,8 +279,8 @@
 # Define overall pipeline
 ##############################
-.auto_deploy_kubernetes: &auto_deploy_kubernetes
-  <<: *kubernetes-deploy
+.auto_deploy: &auto_deploy
+  <<: *auto_deploy_image
   stages:
     - build
@@ -290,6 +292,10 @@
   build:
     <<: *build_branches
+  # Choose between:
+  # *manual_deploy_to_production
+  # *auto_deploy_to_production
+  # *auto_deploy_tags_to_production
   production:
     <<: *manual_deploy_to_production
@@ -302,9 +308,11 @@
   stop_review:
     <<: *stop_review
-# -----------------------------------------
-<<: *auto_deploy_kubernetes
+##############################
+# Project's `.gitlab-ci.yml`
+##############################
+<<: *auto_deploy
 variables:
   # Application deployment domain