fix

Author: reakaleek

.github/workflows/preview.yml

@@ -28,7 +28,7 @@ jobs:
                 issue_number: context.issue.number,
                 owner: context.repo.owner,
                 repo: context.repo.repo,
-                ref: ${{ github.event.pull_request.head.ref }},
+                ref: "${{ github.event.pull_request.head.ref }}",
                 transient_environment: true,
                 environment: `preview-${context.issue.number}`,
                 description: `Preview deployment for PR ${context.issue.number}`,