Fail the test run due to logging after teardown

Fail the test run run with exit code 1 if logging occurs after teardown.
#7731 prints warnings if this happens, but failing the run because of it is a breaking change and can thus only be done in the next major.

@SimenB can you create a Jest 25 milestone and add this to it?
Thought this was better to keep track than just the TODO comment in the source code.