Issue #11653: fix -W with -j in regrtest.

diff --cc Lib/test/regrtest.py
Simple merge

diff --cc Misc/NEWS
index 0a42987413d27fe58c940df6005dcc7cca1b7980,2c79a71abec94d905700f5ec21657450b336f60c..a6ae16a7b659c94291d694aba4e504577b4c0894
--- 1/Misc/NEWS
--- 2/Misc/NEWS
+++ b/Misc/NEWS
@@@ -293,16 -161,10 +293,18 @@@ Tools/Demo
  Tests
  -----
  
+ - Issue #11653: fix -W with -j in regrtest.
+ 
 +- The email test suite now lives in the Lib/test/test_email package.  The test
 +  harness code has also been modernized to allow use of new unittest features.
 +
 +- regrtest now discovers test packages as well as test modules.
 +
  - Issue #11577: improve test coverage of binhex.py. Patch by Arkady Koplyarov.
  
 +- New test_crashers added to exercise the scripts in the Lib/test/crashers
 +  directory and confirm they fail as expected
 +
  - Issue #11578: added test for the timeit module.  Patch Michael Henry.
  
  - Issue #11503: improve test coverage of posixpath.py. Patch by Evan Dandrea.