Change unittest.__main__ to use import os.path

Lib/unittest/__main__.py

@@ -2,8 +2,7 @@
 
 import sys
 if sys.argv[0].endswith("__main__.py"):
-    # FIXME change to `import os.path` as it was for cpython once `import os.path` works
-    import os
+    import os.path
     # We change sys.argv[0] to make help message more useful
     # use executable without path, unquoted
     # (it's just a hint anyway)