push docker image only tag v*

Author: fchastanet

.github/workflows/docker.yml

@@ -26,7 +26,7 @@ jobs:
         uses: docker/setup-buildx-action@v1
 
       - name: Log in to Docker Hub
-        if: github.event_name != 'pull_request'
+        if: startsWith(github.ref, 'refs/tags/v')
         uses: docker/login-action@v1
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
@@ -58,7 +58,7 @@ jobs:
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
           # build on feature branches, push only on master branch
-          push: ${{ github.ref == 'refs/heads/master' }}
+          push: ${{ startsWith(github.ref, 'refs/tags/v') }}
 
       - name: Image digest
         run: echo ${{ steps.docker_build.outputs.digest }}