No need to send stderr to NULL in test, and in fact this may hide errors

Author: rianhunter

Lib/test/test_asyncio/test_subprocess.py

@@ -894,8 +894,7 @@ def test_subprocess_break_pipe(self):
         # See https://github.com/python/cpython/issues/130925
         async def main():
             proc = await asyncio.create_subprocess_exec(*PROGRAM_YES,
-                                                        stdout=asyncio.subprocess.PIPE,
-                                                        stderr=asyncio.subprocess.DEVNULL)
+                                                        stdout=asyncio.subprocess.PIPE)
             try:
                 # just make sure the program has executed correctly
                 data = await proc.stdout.readline()