fix: use gh cli to checkout to pr

Author: steveiliop56

.github/workflows/preview.yml

@@ -15,13 +15,18 @@ concurrency: preview-${{ github.ref }}
 jobs:
   deploy-preview:
     runs-on: ubuntu-latest
-    if: github.event.action != 'closed' && (github.event.issue.pull_request && contains(github.event.comment.body, '@preview deploy'))
+    if: github.event.action != 'closed' || (github.event.issue.pull_request && contains(github.event.comment.body, '/preview'))
     steps:
       - name: Checkout
         uses: actions/checkout@v4
         with:
           fetch-depth: 0
-          ref: ${{ github.head_ref}}
+
+      - name: Checkout Pull Request
+        if: github.event.issue.pull_request && contains(github.event.comment.body, '/preview')
+        run: hub pr checkout ${{ github.event.issue.number }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Setup bun
         uses: oven-sh/setup-bun@v2