meson: Avoid using setup.py directly for the installation
setuptools 68.0.0 recommend:
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Please avoid running ``setup.py`` directly.
Instead, use pypa/build, pypa/installer or other
standards-based tools.
See https://blog.ganssle.io/articles/2021/10/setup-py-deprecated.html for details.
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...
!!
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Please avoid running ``setup.py`` and ``easy_install``.
Instead, use pypa/build, pypa/installer or other
standards-based tools.
See https://github.com/pypa/setuptools/issues/917 for details.
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!!
At Fluendo we also found the behavior of setup.py install --prefix
on osX Python installed with homebrew is not correct.
I would like to work in this issue on the next GStreamer hackfest.