ci/image: Set tag to latest

Author: bilelmoussaoui

.github/workflows/image.yml

@@ -40,6 +40,9 @@ jobs:
         uses: docker/metadata-action@9ec57ed1fcdbf14dcef7dfbe97b2010124a938b7
         with:
           images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          tags: |
+            # set latest tag for master branch
+            type=raw,value=latest,enable=${{ github.ref == format('refs/heads/{0}', 'master') }}
 
       - name: Build and push Docker image
         uses: docker/build-push-action@f2a1d5e99d037542a71f64918e516c093c6f3fc4