use comma separation

.github/workflows/container-build.yml

@@ -43,7 +43,7 @@ jobs:
           tags = "${{ inputs.tags }}".split(",")
           full_image = [f"{image}:py{version}-{tag.strip()}" for tag in tags]
           with open(os.environ['GITHUB_OUTPUT'], 'a') as file:
-              file.write(f"tags={'\n'.join(full_image)}")
+              file.write(f"tags={', '.join(full_image)}")
           EOF
 
       - name: Build image and export to Docker