Python-3: assertNotIn(..response.content) -> assertNotContains

cms/djangoapps/contentstore/tests/tests.py

lms/djangoapps/branding/tests/test_page.py

lms/djangoapps/certificates/tests/test_webview_views.py

lms/djangoapps/courseware/tests/test_date_summary.py

lms/djangoapps/courseware/tests/test_views.py

lms/djangoapps/instructor/tests/test_ecommerce.py

lms/djangoapps/instructor/tests/test_email.py

lms/djangoapps/instructor/tests/test_proctoring.py

...oapps/instructor/tests/views/test_instructor_dashboard.py

openedx/features/announcements/tests/test_announcements.py

...es/course_duration_limits/tests/test_course_expiration.py

...eatures/course_experience/tests/views/test_course_home.py