ci: exclude forks

Author: Kikobeats

.github/workflows/update.yml

@@ -8,7 +8,7 @@ env:
 jobs:
   update-lockfile:
     runs-on: ubuntu-latest
-    if: ${{ github.actor == 'dependabot[bot]' }}
+    if: ${{ github.actor == 'dependabot[bot]' && github.event.pull_request.head.repo.fork == false }}
     permissions:
       pull-requests: write
       contents: write