fix github action branch name

Author: cDanowski

.github/workflows/dockerhub-fix-mandant-classification.yml

@@ -4,7 +4,7 @@ name: CI to Docker Hub - Snapshot fix classification - mandant version
 on:
   # Triggers the workflow on push or pull request events but only for the master branch
   push:
-    branches: [ fix/mandant-classification ]
+    branches: [ fix/mandant-classification-improvement ]
 
   # Allows you to run this workflow manually from the Actions tab
   workflow_dispatch: