[BUGFIX] Correct gh pages deployment

Author: benjaminkott

.github/workflows/site.yml

@@ -14,6 +14,8 @@ jobs:
     name: Deploy
     runs-on: ubuntu-latest
     if: github.repository == 'typo3/typo3.icons'
+    permissions:
+      contents: write
 
     steps:
       - name: Checkout Code