No win95 tests after commit "tests: Add a helper routine to wait for a child process and propagate its result correctly."

[Paul Vriens]

Hi,

This commit: 05c7174909e975fc7d0ebf9a59bb07160c09d66d introduces a new helper 
script but uses InterlockedExchangeAdd that is not available on win95.

This means that none of the tests run on win95 anymore.