memfiles: enable test; refs #6361

tests/stdlib/tmemfiles2.nim

@@ -1,10 +1,8 @@
 discard """
   file: "tmemfiles2.nim"
-  disabled: true
   output: '''Full read size: 20
 Half read size: 10 Data: Hello'''
 """
-# doesn't work on windows. fmReadWrite doesn't create a file.
 import memfiles, os
 var
   mm, mm_full, mm_half: MemFile