Specify head ref in dependabot PR workflow (#347)

Signed-off-by: Thomas Farr <[email protected]>

Author: Xtansia

.github/workflows/dependabot_pr.yml

@@ -27,6 +27,8 @@ jobs:
         uses: actions/checkout@v4
         with:
           token: ${{ steps.github_app_token.outputs.token }}
+          ref: ${{ github.event.pull_request.head.ref }}
+          repository: ${{ github.event.pull_request.head.repo.full_name }}
 
       - name: Update the changelog
         uses: dangoslen/dependabot-changelog-helper@v4