Change default tag in pull requests

.github/workflows/build.yml

@@ -42,6 +42,13 @@ jobs:
           echo "IMAGE_REGISTRY=${IMAGE_REGISTRY,,}" >> ${GITHUB_ENV}
           echo "IMAGE_NAME=${IMAGE_NAME,,}" >> ${GITHUB_ENV}
 
+      - name: Set tag to pr if pull request
+        if: github.event_name == 'pull_request'
+        env:
+          PULL_REQUEST_NUMBER: ${{ github.event.number }} 
+        run: |
+          echo "DEFAULT_TAG=pr-${}" >> ${GITHUB_ENV}
+
       - name: Setup Podman
         shell: bash
         run: |
@@ -76,10 +83,9 @@ jobs:
           # This generates all the tags for your image, you can add custom tags here too!
           # Default tags are "$DEFAULT_TAG" and "$DEFAULT_TAG.$date".
           tags: |
-            type=raw,value=${{ env.DEFAULT_TAG }},enable=${{ ! (github.event_name == 'pull_request') }}
+            type=raw,value=${{ env.DEFAULT_TAG }}
             type=raw,value={{date 'YYYYMMDD'}}
             type=sha,enable=${{ github.event_name == 'pull_request' }}
-            type=ref,event=pr
           labels: |
             io.artifacthub.package.readme-url=https://raw.githubusercontent.com/${{ github.repository_owner }}/${{ env.IMAGE_NAME }}/refs/heads/main/README.md
             org.opencontainers.image.created=${{ steps.date.outputs.date }}