Time to do this — Python 2 is EOL. This exposed a bug in one of the
tests that was stripping the entire environment from its subprocesses
(though they did sort of work on Python 2).
The reaping test assumes that all the `sleep` processes on the system
are created by us, which is an incorrect assumption, and creates
problems now that we run in a more "complete" system in CI (i.e. not in
a minimal container).
This solves the issue by not assuming that random sleep processes are
related to us: instead, we look at whether these processes are in our
process group.
This also includes a little clean up of the reaping stage 1.
Using the child subreaper mechanism, we can actually run
tests inside the CI environment without depending on Docker.
While this does not replace the existing tests, it allows
at least some functional coverage within CI.
Thomas Orozco
Thomas Orozco