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It complains about duplicate import lines and I don't want to abstract
them now.

For this to work, you have to put this project (GTK) and Android's
project into one directory and call the Android's folder
"briar-android".

Although I find YAML a lot better, GNOME Builder sadly doesn't support
it: https://gitlab.gnome.org/GNOME/gnome-builder/issues/520

This essentially reverts 5fc6b517, but
also updates some dependencies.

Also move shared pytest fixtures to conftest.py

https://docs.python.org/3/library/random.html#random.choices

Also randomly generate an auth_token now.

https://github.com/PyCQA/pylint/issues/2108