fix: Reduce GitHub Action PR preview permissions (#62)

Author: marissamarym

.github/workflows/preview-docs.yml

@@ -5,7 +5,9 @@ on: pull_request
 jobs:
   run:
     runs-on: ubuntu-latest
-    permissions: write-all
+    permissions:
+      contents: read
+      pull-requests: write
     steps:
       - name: Checkout repository
         uses: actions/checkout@v4