Update Instructor Dashboard tests to use SharedModuleStoreTestCase.
Update Instructor Dashboard tests to use SharedModuleStoreTestCase.

Also added reset_test_case() and @modifies_courseware to SharedModuleStoreTestCase.

Revert "More verbose test builds in Jenkins, for debugging."

This reverts commit 58cade4cc4288335026649470a48b7bbca969ee8.

bmedx/modulestore,bmedx/modulestore,bmedx/modulestore