ci: use branch name as tag

.github/workflows/ci.yaml

@@ -1,6 +1,8 @@
 name: Build container
 on:
   push:
+  pull_request:
+    branches: [ "main" ]
   schedule:
     - cron: '0 16 * * FRI'
 
@@ -13,14 +15,14 @@ jobs:
         uses: redhat-actions/buildah-build@v2
         with:
           image: ${{ github.actor }}/${{ github.event.repository.name }}
-          tags: latest
+          tags: ${{ github.ref_name }}
           containerfiles: |
             ./Containerfile
       - name: Push
         uses: redhat-actions/push-to-registry@v2
         with:
           image: ${{ github.actor }}/${{ github.event.repository.name }}
-          tags: latest
+          tags: ${{ github.ref_name }}
           # extra-args: --compression-format zstd:chunked
           registry: ghcr.io
           username: ${{ github.actor }}