The loops in this disabled test are executed a random number of times that may be zero.

Purpose of this ticket is to re-enable the test and make sure that the loops get all executed at least once.

This test is around from ages, so someone may wonder: why did it start failing only some time ago? It turns out that SERVER-72031 added an additional call to rand() happening before the failing unit test, shifting by one the quite deterministic sequence of generated values.

So the conclusion is: rand() is not that that random after all. Let's always use PseudoRandom that is really generating random values via XorShift128.