hghave: disallow symlinks on Windows Symlinks on Windows require either a special priviledge, or enabling Developer Mode. It's probably the latter that is enabled on the new CI machine. But since Mercurial itself is saying no to symlinks on Windows, the tests for symlinks shouldn't be attempted. This should fix a lot of the noise in the py3 tests. Differential Revision: https://phab.mercurial-scm.org/D7233