Problematic tests

[dgarijo]

I did a fresh install of inspect4py from the dev branch. There are 2 problematic tests:

FAILED test_inspect4py.py::Test::test_metadata - AssertionError: assert {'allow_forki...{/user}', ...} == {}
FAILED test_inspect4py.py::Test::test_multiple_mains - assert 0 == 2

These should be reviewed (no critical functionality, but important that they work)