[issue43867] concurrent.futures: handle explicitly SystemExit in managers.Server

Change by STINNER Victor : -- keywords: +patch pull_requests: +24171 stage: -> patch review pull_request: https://github.com/python/cpython/pull/25441 ___ Python tracker ___ _

[issue43867] concurrent.futures: handle explicitly SystemExit in managers.Server

New submission from STINNER Victor : In bpo-43843, I modified libregrtest to log a warning if a thread raises an uncaught exception. test_concurrent_futures now logs two warnings. s390x Debian 3.x: https://buildbot.python.org/all/#/builders/49/builds/1124 AMD64 RHEL7 3.x: https://buildbot.pyt