Update build_changelog.yml

Signed-off-by: Henrique Graca <999396+hjgraca@users.noreply.github.com>

Author: hjgraca

.github/workflows/build_changelog.yml

@@ -4,9 +4,9 @@ name: Build changelog
 on:
   workflow_dispatch:
 
-permissions:
-  contents: write
-
 jobs:
   changelog:
+    permissions:
+      contents: write       # create temporary branch to store changelog changes
+      pull-requests: write  # create PR with changelog changes
     uses: ./.github/workflows/reusable_publish_changelog.yml