set gitsync to release branch and stackable version to 25.11

Author: maltesander

demos/argo-cd-git-ops/manifests/airflow/airflow.yaml

@@ -19,7 +19,7 @@ spec:
     # TODO(@maltesander): In a Stackable release, this branch should point to the release-YY.MM branch!
     dagsGitSync:
       - repo: https://github.com/stackabletech/demos/
-        branch: main
+        branch: release-25.11
         gitFolder: "demos/argo-cd-git-ops/dags"
         depth: 2
     volumes:

stacks/stacks-v2.yaml

@@ -36,7 +36,7 @@ stacks:
       - name: stackableReleaseVersion
         description: The Stackable release to be installed via Argo. This replaces the demo `stackableRelease` parameter.
         # TODO(@maltesander): Must be adapted in case of release !
-        default: 0.0.0-dev
+        default: 25.11
       - name: argocdAdminPassword
         description: Password of the ArgoCD admin user.
         # generated via: `htpasswd -nbBC 10 "" adminadmin | tr -d ':\n'`