* feat(ooniprobe): discard lists not in selected categories
One day we may make an integration mistake and for any reason
we may end up with URLs that do not belong to the categories
originally selected by the user. If that happens, it's nice to
have a safety net where we remove URLs that do not belong to
the right category before proceeding with testing.
This diff was conceived while discussing the robustness of
https://github.com/ooni/probe/issues/1299 with @hellais.
* fix behavior and add unit test
* more robust
