Python 3: resp.content regex searches

cms/djangoapps/contentstore/tests/test_contentstore.py

cms/djangoapps/contentstore/tests/tests.py

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

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

lms/djangoapps/branding/tests/test_page.py

lms/djangoapps/branding/tests/test_views.py

lms/djangoapps/courseware/tests/test_about.py

lms/djangoapps/courseware/tests/test_course_info.py

lms/djangoapps/courseware/tests/test_entrance_exam.py

lms/djangoapps/courseware/tests/test_password_reset.py

lms/djangoapps/courseware/tests/test_tabs.py

lms/djangoapps/courseware/tests/test_views.py

lms/djangoapps/discussion/tests/test_views.py

lms/djangoapps/instructor/tests/test_api.py

lms/djangoapps/shoppingcart/tests/test_payment_fake.py

lms/djangoapps/shoppingcart/tests/test_views.py

lms/djangoapps/survey/tests/test_views.py

openedx/core/djangoapps/enrollments/tests/test_views.py