3rd party repos policy: abstract the diverse repos clause
The policy states that 3rd party repos shouldn't include "diverse
repos". The principle here is that Fedora should retain control
of the software that's being made available, as opposed to
enabling repos that are out of our control and whose behaviour
is risk-prone.
It is helpful to restate this "diverse repos" clause in a more
generic manner, in order to enable other mechanisms for managing
3rd party repos, while remaining true to the intent of the policy.
For example, a working group could use a whitelist to control
which software is made available from a larger repository.