Merge pull request #14399 from edx/ormsbee/csm_crawler_locking

lms/djangoapps/courseware/model_data.py

lms/djangoapps/courseware/module_render.py

lms/djangoapps/courseware/tests/test_views.py

lms/djangoapps/courseware/views/index.py

lms/envs/common.py

openedx/core/djangoapps/crawlers/__init__.py

openedx/core/djangoapps/crawlers/admin.py

openedx/core/djangoapps/crawlers/migrations/0001_initial.py

openedx/core/djangoapps/crawlers/migrations/__init__.py

openedx/core/djangoapps/crawlers/models.py

openedx/core/djangoapps/crawlers/tests.py