It's good enough to run the test on macOS and linux.
The test takes very long on Windows because the * may expand to a path longer than 260 characters.
In Windows %t might end up very close to the maximum path length of 260
characters. It is possible to use extended lenght paths with a \\?\
prefix. The changes introduce %long-tmp for cases that the test suite
is going over those limits and need a hint in Windows that the path
might be long. It expands to the same as %t in other platforms.
This should fix the test/Misc/stats_dir_profiler.swift in the Windows
VS 2017 CI machines and hopefully not affect anything else.
