Repo checks: skip docstring checks if not in the diff (#32328)

* tmp

* skip files not in the diff

* use git.Repo instead of an external subprocess

* add tiny change to confirm that the diff is working on pushed changes

* add make quality task

* more profesh main commit reference

.circleci/config.yml

@@ -142,6 +142,7 @@ jobs:
             - run: python utils/custom_init_isort.py --check_only
             - run: python utils/sort_auto_mappings.py --check_only
             - run: python utils/check_doc_toc.py
+            - run: python utils/check_docstrings.py --check_all
 
     check_repository_consistency:
         working_directory: ~/transformers
@@ -190,4 +191,4 @@ workflows:
             - check_circleci_user
             - check_code_quality
             - check_repository_consistency
-            - fetch_all_tests
+            - fetch_all_tests