Add a mode to burn_in_tests that will detect changes to test suites and run the entire suite multiple times.

As a Server Engineer,
I want changed test suites to be detected and run by burn_in_tests,
So that I can feel confident my changes do not introduce reliability issues.

AC:

• Changes to test suites cause the entire suite to be run multiple times by burn_in_tests.
• New test suites are run multiple times by burn_in_tests.

See project scope here.