* Revert "Reverted "Fixed #33213 -- Doc'd testing code coverage in parallel and used it.""
This reverts commit 78da5ca0c1.
* Restored coverage multiprocess concurrency with threads
Investigating https://github.com/nedbat/coveragepy/issues/1585 revealed
that thread tracing gets disabled when passing
`concurrency = multiprocessing`. Adding `thread` restores it, and
ensures that the `auser()` is reported as covered since the test suite
uses `AsyncToSync` to execute this middleware (which spawns threads).
By providing a .coveragerc file with all default settings, users only
have to execute "coverage run ./runtests.py" without the need to specify
all the possible flags. The same applies to "coverage html" and
"coverage xml".
This only affests reporting not data collection and allows coverage.py
to succesfully finish the generation of e.g. the HTML report.
Cases of code whose execution data is collected during the run phase but
for which no associated source code files can be found at the reporting
phase include tests with egg files and Python module files created at
test execution-time.
