test: fix Python unittests in ./test and ./tools

Co-authored-by: @patrickhousley

Fixes to Python tests to ensure that the following all pass:
1. __python2 -m pytest ./test ./tools__  # 30 tests pass
2. __python3 -m pytest ./test ./tools__  # 30 tests pass
3. __python2 -m unittest discover -s ./test/tools__  # 1 test passes
4. __python3 -m unittest discover -s ./test/tools__  # 1 test passes
5. __PYTHON=python2 make tooltest__   # 1 test passes
6. __PYTHON=python3 make tooltest__   # 1 test passes

This is a subset of #30033

PR-URL: https://github.com/nodejs/node/pull/30340


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: David Carlier <devnexen@gmail.com>