Unit test for import performance STUD-1994
Fix is_browser_on_page method for Studio Container page
Merge pull request #4534 from edx/nimisha/import-perf-unit-test-STUD-1994

Unit test for import performance STUD-1994
Merge pull request #4552 from edx/zoldak/studio-container-page

Improve is_browser_on_page method for Studio Container page
BLD-1104: List units that use group configuration.
REVERT THIS COMMIT BEFORE MERGE.
Addressed comments.