New step to extract branch name

.github/workflows/ci.yml

@@ -135,6 +135,11 @@ jobs:
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v1
 
+      - name: Extract branch name
+        shell: bash
+        run: echo "##[set-output name=branch;]$(echo ${GITHUB_REF#refs/heads/})"
+        id: extract_branch
+
       - name: Generating release tags and labels
         if: github.event_name == 'release'
         id: release_meta
@@ -152,7 +157,7 @@ jobs:
         uses: docker/metadata-action@v4
         with:
           images: jaedb/iris
-          tags: ${{ github.ref }}
+          tags: ${{ steps.extract_branch.outputs.branch }}
 
       - name: Login to DockerHub
         uses: docker/login-action@v1