tests: also skip remotefilelog *.py tests on Windows

Otherwise, the buildbot won't even be green on stable with the RC.  This should
have gone with 0800d9e6e216.  Previous discussion in this thread:

https://www.mercurial-scm.org/pipermail/mercurial-devel/2018-November/125421.html

tests/test-remotefilelog-datapack.py

@@ -373,4 +373,6 b' class datapacktests(datapacktestsbase, u'
 # - GC two packs into one
 
 if __name__ == '__main__':
+    if pycompat.iswindows:
+        sys.exit(80)    # Skip on Windows
     silenttestrunner.main(__name__)

tests/test-remotefilelog-histpack.py

@@ -273,4 +273,6 b' class histpacktests(unittest.TestCase):'
 # - repack two packs into one
 
 if __name__ == '__main__':
+    if pycompat.iswindows:
+        sys.exit(80)    # Skip on Windows
     silenttestrunner.main(__name__)