adds shell.

action.yml

@@ -8,8 +8,10 @@ runs:
       # to github, dockerhub and sonar.
       - name: Build and test with Maven in docker
         run: ./mvn.sh clean verify
+        shell: bash
       - name: Deploy Maven Artifacts
         run: ./mvn.sh deploy
+        shell: bash
       - name: Notify dedicated teams channel of Success
         uses: dragos-cojocari/ms-teams-notification@v1.0.0
         if: ${{ success() }}