regrtest.py: disable replace_stdout() on Windows until it is fixed

See issue #8533 (problem with newlines on Windows).

Lib/test/regrtest.py

@@ -733,6 +733,9 @@ def findtests(testdir=None, stdtests=STDTESTS, nottests=NOTTESTS):
 def replace_stdout():
     """Set stdout encoder error handler to backslashreplace (as stderr error
     handler) to avoid UnicodeEncodeError when printing a traceback"""
+    if os.name == "nt":
+        # Replace sys.stdout breaks the stdout newlines on Windows: issue #8533
+        return
     stdout = sys.stdout
     sys.stdout = open(stdout.fileno(), 'w',
         encoding=stdout.encoding,