The PYTHONDONTWRITEBYTECODE trick is no longer necessary with PEP 517

[1] https://archlinux.org/todo/use-pyprojecttoml-for-building-if-supported/
[2] https://rfc.archlinux.page/0020-sources-for-python-packaging/

Tests are included in the PyPI sdist since [1].

Also makes tests less verbose.

[1] https://github.com/ojarva/python-sshpubkeys/pull/58

The latter is deprecated since setuptools 41.5.0 [1].

[1] https://github.com/pypa/setuptools/blob/v41.5.0/CHANGES.rst#v4150

This will be a new dependency in the next version of moto [1].

As a side note, there is moto 1.3.9 on PyPI, while it is actually accidentally released [2].

[1] https://github.com/spulec/moto/pull/2108
[2] https://github.com/spulec/moto/issues/640#issuecomment-507486727