use a repo-scoped personal access token (#2193)

Author: JoshMock

.github/workflows/serverless-patch.yml

@@ -42,6 +42,7 @@ jobs:
         run: $GITHUB_WORKSPACE/stack/.github/workflows/serverless-patch.sh
       - uses: peter-evans/create-pull-request@v6
         with:
+          token: ${{ secrets.GH_TOKEN }}
           path: serverless
           title: 'Apply patch from elastic/elasticsearch-js#${{ github.event.pull_request.number }}'
           commit-message: 'Apply patch from elastic/elasticsearch-js#${{ github.event.pull_request.number }}'