chore: update publish-docs permissions to be more targeted. (#812)

This is recommended by OSSF.

Author: maciej-kisiel

.github/workflows/publish-docs.yml

@@ -5,11 +5,12 @@ on:
     types: [published]
   workflow_dispatch:
 
-permissions:
-  contents: write
+permissions: read-all
 
 jobs:
   deploy:
+    permissions:
+      contents: write
     runs-on: ubuntu-latest
     steps:
       - name: Check out code