Dont revalidate on windows

[casperisfine]

Hoping to fix:

 1) Failure:
CompileCacheHandlerErrorsTest#test_input_to_output_unexpected_type [test/compile_cache_handler_errors_test.rb:61]:
not all expectations were satisfied
unsatisfied expectations:
- expected exactly once, invoked never: Bootsnap::CompileCache::ISeq.input_to_output(any_parameters)
- expected exactly once, invoked never: Bootsnap::CompileCache::ISeq.input_to_storage(any_parameters)

To be fair that test is a bit weird, but I don't really have much ways to debug windows anyway.

[casperisfine]

Hum, retrying the failed build worked, so maybe it was a fluke of some sort? I'll keep this as a draft for now.