Creating an umbrella ticket to track efforts to refactor test and test utils for ease of development.
https://issues.apache.org/jira/browse/HUDI-996: shared spark session provider.
https://issues.apache.org/jira/browse/HUDI-995 Organize test utils methods and classes
https://issues.apache.org/jira/browse/HUDI-994 : Identify functional tests that are convertible to unit tests with mocks
https://issues.apache.org/jira/browse/HUDI-736 : Simplify ReflectionUtils#getTopLevelClasses
https://issues.apache.org/jira/browse/HUDI-488 : Refactor Source classes in hudi-utilities