refactor: Use upstream reusable workflow directly

Author: billnapier

.github/workflows/license-check.yml

@@ -31,17 +31,9 @@ jobs:
             exit 1
           fi
 
-      # The reusable workflow is in a different repository, so we check it out.
-      # Assuming 'billnapier/licenseclassifier' is the repository on GitHub.
-      - name: Check out licenseclassifier repository
-        uses: actions/checkout@v3
-        with:
-          repository: billnapier/licenseclassifier
-          path: ./.licenseclassifier
-
       - name: Run license classifier
         id: classify
-        uses: ./.licenseclassifier/.github/workflows/classify.yml
+        uses: google/licenseclassifier/.github/workflows/classify.yml@main
         with:
           file_to_classify: ${{ steps.find_license.outputs.filename }}