ci: fix dependabot errors

Author: seratch

.github/workflows/pr-labels.yml

@@ -98,7 +98,7 @@ jobs:
           mkdir -p "$output_dir"
           echo "output_file=${output_file}" >> "$GITHUB_OUTPUT"
       - name: Run Codex labeling
-        if: ${{ github.event_name == 'workflow_dispatch' || steps.pr.outputs.is_fork != 'true' }}
+        if: ${{ (github.event_name == 'workflow_dispatch' || steps.pr.outputs.is_fork != 'true') && github.actor != 'dependabot[bot]' }}
         uses: openai/codex-action@f5c0ca71642badb34c1e66321d8d85685a0fa3dc
         with:
           openai-api-key: ${{ secrets.PROD_OPENAI_API_KEY }}