test_multiprocessing.test_empty_authkey triggers env changed failure #116439
Description
The test starts a thread but doesn't join it, which can lead to test failures with "ENV CHANGED"
cpython/Lib/test/_test_multiprocessing.py
Lines 3518 to 3521 in c62144a
See also #25845
From https://buildbot.python.org/all/#/builders/249/builds/7957/steps/5/logs/stdio:
...
test_empty_authkey (test.test_multiprocessing_fork.test_processes.WithProcessesTestListener.test_empty_authkey) ... ok
test_multiple_bind (test.test_multiprocessing_fork.test_processes.WithProcessesTestListener.test_multiple_bind) ... ok
Warning -- Dangling threads: {<Thread(Thread-13 (run), started 139968890533568)>}
...