feat: pipeline container build

.github/workflows/example.yml

@@ -1,6 +1,9 @@
 name: Sample Testing
 on: [push]
 
+env:
+  VER: 0.1.2
+
 jobs:
   my_job:
     runs-on: stackit-docker
@@ -8,7 +11,7 @@ jobs:
     steps:
     - name: First Chat Message
       if: ${{ always() }}
-      uses: https://stackit-solutions.git.onstackit.cloud/actions/notify@v0.1.2
+      uses: https://stackit-solutions.git.onstackit.cloud/actions/notify@v${{ env.VER }}
       with:
         title: "[START] sample test (${{ forgejo.run_number }})"
         author: ${{ forgejo.actor }}