Move CI_IMAGE to external snippet via !reference #2890

cumulus/.gitlab-ci.yml

@@ -26,7 +26,7 @@ variables:
   GIT_STRATEGY: fetch
   GIT_DEPTH: 100
   CARGO_INCREMENTAL: 0
-  CI_IMAGE: "paritytech/ci-unified:bullseye-1.70.0-2023-05-23"
+  CI_IMAGE: !reference [.ci-unified, variables, CI_IMAGE]  
   DOCKER_OS: "debian:stretch"
   ARCH: "x86_64"
   ZOMBIENET_IMAGE: "docker.io/paritytech/zombienet:v1.3.55"
@@ -150,8 +150,12 @@ include:
   - scripts/ci/gitlab/pipeline/zombienet.yml
   # timestamp handler
   - project: parity/infrastructure/ci_cd/shared
-    ref: v0.2
+    ref: main
     file: /common/timestamp.yml
+  - project: parity/infrastructure/ci_cd/shared
+    ref: main
+    file: /common/ci-unified.yml  
+
 
 #### stage:                        .post