Update /tmp/images/ci_files/variables.yml for 12.0.6

ci_files/variables.yml

 ---
 variables:
   GITLAB_ELASTICSEARCH_INDEXER_VERSION: v1.2.0
-  GITLAB_VERSION: v12.0.3
-  GITLAB_REF_SLUG: v12.0.3
-  GITLAB_ASSETS_TAG: v12.0.3
+  GITLAB_VERSION: v12.0.6
+  GITLAB_REF_SLUG: v12.0.6
+  GITLAB_ASSETS_TAG: v12.0.6
   GITLAB_MONITOR_VERSION: 4.0.0
   GITLAB_SHELL_VERSION: v9.3.0
   GITLAB_WORKHORSE_VERSION: v8.7.0
-  GITALY_VERSION: v1.49.0
+  GITALY_VERSION: v1.47.2
   GIT_VERSION: 2.21.0
   GO_VERSION: 1.11.5
   KUBECTL_VERSION: v1.9.3