fix: use the branch name instead of HEAD

I have no idea why after checkout 'HEAD' sha is not the same as  `origin/head_ref` but whatever

Author: nbrugger-tgm

.github/workflows/test_action.yml

@@ -14,7 +14,7 @@ jobs:
       - name: Capture commit id
         id: capture
         run: |
-          COMMIT_ID=$(git rev-parse HEAD)
+          COMMIT_ID=$(git rev-parse origin/${{ github.head_ref }})
           echo "The sha of the starting commit is $COMMIT_ID"
           echo "::set-output name=commit::$COMMIT_ID"
       - name: create test commit