[ci] add variable for ubuntu version, can be passed from dumux

.gitlab-ci.yml

@@ -2,19 +2,40 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 
 stages:
+  - variables-parser
   - check-status
   - trigger pipelines
 
 variables:
-  DUMUX_DOCKER_CI_BRANCH: master
   IMAGE_REGISTRY_URL: $CI_REGISTRY/dumux-repositories/dumux-docker-ci
   DUMUX_CI_DUNE_LATEST_RELEASE: "2.9"
 
+variables-parse-job:
+  image: $IMAGE_REGISTRY_URL/alpine
+  stage: variables-parser
+  rules:
+  - if: $CI_PIPELINE_SOURCE == "pipeline"
+    when: always
+  - if: $CI_PIPELINE_SOURCE == "merge_request_event"
+    when: always
+  script:
+    - |
+      DUMUX_DOCKER_CI_BRANCH=${DUMUX_DOCKER_BRANCH:-master}
+      UBUNTU_VERSION=${DUMUX_UBUNTU_VERSION:-22.04}
+      IMAGE_NAME="${DUMUX_DOCKER_CI_BRANCH}_full"
+      IMAGE="$IMAGE_REGISTRY_URL/${IMAGE_NAME}:dune-$DUMUX_CI_DUNE_LATEST_RELEASE-gcc-ubuntu-$UBUNTU_VERSION"
+      echo "IMAGE=$IMAGE" | tee -a dynamic-variables.env
+      echo "UBUNTU_VERSION=$UBUNTU_VERSION" | tee -a dynamic-variables.env
+      echo "DUMUX_DOCKER_CI_BRANCH=$DUMUX_DOCKER_CI_BRANCH" | tee -a dynamic-variables.env
+  artifacts:
+    reports:
+      dotenv: dynamic-variables.env
+
 # for commits happening on master, we check if there was a successful
 # pipeline on a related merge request already. If yes, we simply return
 # to propagate that pipeline status on master. Otherwise, we trigger a new run.
 check-pipeline-status:
-  image: $IMAGE_REGISTRY_URL/${DUMUX_DOCKER_CI_BRANCH}_full:dune-2.9-gcc-ubuntu-22.04
+  image: $IMAGE_REGISTRY_URL/alpine
   stage: check-status
   rules:
     - if: $CI_PIPELINE_SOURCE == "schedule"
@@ -70,9 +91,6 @@ check-pipeline-status:
       - local: .gitlab-ci/default.yml
     strategy: depend
   rules:
-  - if: $DUMUX_DOCKER_BRANCH != null
-    variables:
-      DUMUX_DOCKER_CI_BRANCH: $DUMUX_DOCKER_BRANCH
   - if: $CI_PIPELINE_SOURCE == "pipeline"
     when: always
   - if: $CI_PIPELINE_SOURCE == "merge_request_event"
@@ -89,5 +107,4 @@ check-pipeline-status:
 full-dune-latest-release-gcc:
   extends: .default-trigger
   variables:
-    IMAGE_NAME: "${DUMUX_DOCKER_CI_BRANCH}_full"
-    IMAGE: "$IMAGE_REGISTRY_URL/$IMAGE_NAME:dune-$DUMUX_CI_DUNE_LATEST_RELEASE-gcc-ubuntu-22.04"
+    IMAGE: $IMAGE