Save or update course video image - TNL-6762

cms/djangoapps/contentstore/tests/test_contentstore.py

cms/djangoapps/contentstore/views/tests/test_videos.py

cms/djangoapps/contentstore/views/videos.py

cms/envs/aws.py

cms/envs/common.py

cms/envs/test.py

cms/urls.py

common/lib/xmodule/xmodule/tests/test_video.py

common/lib/xmodule/xmodule/video_module/video_module.py

lms/djangoapps/courseware/tests/test_video_mongo.py

lms/envs/common.py

requirements/edx/github.txt