as we identified two issues where the goroutine count from before differs from after the test.
1) It seemed like a Go runtime specific Goroutine appeared in rare cases before the test. To avoid this, we introduced a short timeout before looking up the Goroutines.
Another solution might be to do the lookup twice and check if the count matches.
2) A Goroutine that periodically monitors some storage unexpectedly got closed in rare cases. As we could not identify the cause for this, we removed the leaking Goroutines by properly cleaning up.
We observed a race condition that sometimes goroutines are just closing but still measured by the goroutine Lookup of the following test.
We try to avoid this by adding `runtime.Gosched()` at the start of each test.
We observed that sometimes the `pprof.Lookup("goroutine")` resulted in a different goroutine count than `runtime.NumGoroutine()`. It might be due to a race condition, but our usage of both made it impossible to debug.
ChannelReceivesSomething (formerly WaitForChannel) originally was
located in the helpers package.
This move was done to remove a cyclic dependency with the nomand package.
