add concurrent BPS test

The test introduces multiple cycles of Semaphores and
a Fiber for each semaphore blocking and signaling the next.
Through work-stealing the fibers from a cycle should be spread
across different workers and thus test concurrent use of
BinaryPrivateSemaphores.

Cycle of length 3: Sem A -> Sem B -> Sem C -> Sem A -> ...
Algorithm:
	if isFirstInCycle
		signal next

	wait

	if not isFirstInCycle
		signal next