[Bug 56185] The GitLab Windows test job runs even when not needed

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=56185

--- Comment #5 from François Gouget  ---
(In reply to Nikolay Sivov from comment #1)
> It should run them when headers or tools had changed too.

Strictly speaking yes. However 99% of the time header and tool changes don't
impact the tests on Windows and the more test units we run per MR on average,
the fewer test configurations (32/64 bit, Windows versions, GPUs, multi-screen
setups, etc) can be tested. So it's a balancing act unless we can just throw
unlimited resources at the problem (hardware for the VM hosts, Windows VMs and
licenses, administrator time).