Update auto-update.yml

.github/workflows/auto-update.yml

@@ -394,6 +394,7 @@ jobs:
             [1]: https://github.com/iptv-org/iptv/actions/runs/${{ github.run_id }}
           author: 'iptv-bot[bot] <84861620+iptv-bot[bot]@users.noreply.github.com>'
           delete-branch: true
+          base: master
           token: ${{ steps.generate-token.outputs.token }}
       - name: Enable Pull Request Automerge
         if: steps.pr.outputs.pull-request-operation == 'created'