CI: add permissions

Author: azu

.github/workflows/calibreapp-image-actions.yml

@@ -8,6 +8,9 @@ on:
       - '**.jpeg'
       - '**.png'
       - '**.webp'
+permissions:
+  contents: write
+  pull-requests: write
 jobs:
   build:
     # Only run on Pull Requests within the same repository, and not from forks.

.github/workflows/calibreapp-image-manual.yml

@@ -1,6 +1,9 @@
 name: Compress Images
 on:
   workflow_dispatch:
+permissions:
+  contents: write
+  pull-requests: write
 jobs:
   build:
     name: calibreapp/image-actions