[ci] Move additional tests back to test-linux-stable (#1466)

* [ci] Move additional tests back to test-linux-stable

* run slow tests with all tests

* check if test upgrade_version_checks_should_work works

* rm comment

.gitlab-ci.yml

@@ -21,7 +21,7 @@ workflow:
     - if: $CI_COMMIT_BRANCH
 
 variables:
-  CI_IMAGE: "paritytech/ci-unified:bullseye-1.70.0-2023-05-23-v20230706"
+  CI_IMAGE: !reference [.ci-unified, variables, CI_IMAGE]
   # BUILDAH_IMAGE is defined in group variables
   BUILDAH_COMMAND: "buildah --storage-driver overlay2"
   RELENG_SCRIPTS_BRANCH: "master"
@@ -213,6 +213,10 @@ include:
   - project: parity/infrastructure/ci_cd/shared
     ref: v0.2
     file: /common/timestamp.yml
+  # ci image
+  - project: parity/infrastructure/ci_cd/shared
+    ref: main
+    file: /common/ci-unified.yml
 # This job cancels the whole pipeline if any of provided jobs fail.
 # In a DAG, every jobs chain is executed independently of others. The `fail_fast` principle suggests
 # to fail the pipeline as soon as possible to shorten the feedback loop.