Related to WT-5801, it would be nice to have a way to have FlushFileBuffers be a no-op on Windows when running the test suite or other tests.  Like the UNIX "eatmydata" trick, we need to do this without changing source code, only changing the way that it is executed.  I don't believe that preloading a DLL with replacement symbols even possible in Windows, but there are probably some other tricks available.  See discussion in WT-5801.  It looks like this could buy us a 10-15% reduction in run time for the test suite.