.github: workflows: docs: restrict permissions

Restrict permissions explicitly

Signed-off-by: Thomas Stranger <[email protected]>

Author: str4t0m

.github/workflows/docs.yml

@@ -5,6 +5,9 @@ name: Documentation
 
 on: [push, pull_request]
 
+permissions:
+  contents: read
+
 env:
   DOXYGEN_VERSION: 1.9.6
 
@@ -14,6 +17,8 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v4
+        with:
+          persist-credentials: false
 
       - name: Install dependencies
         run: |