setup.py install is deprecated

[bmr-cymru]

Building in Rawhide generates the following warning:

        ********************************************************************************
        Please avoid running ``setup.py`` directly.
        Instead, use pypa/build, pypa/installer, pypa/build or
        other standards-based tools.
        See https://blog.ganssle.io/articles/2021/10/setup-py-deprecated.html for details.
        ********************************************************************************

Our test workflow and RPM builds currently rely on this method of running setup.py.