Fixes #20422: Allow Aggregate and Prefix to filter by family in GraphQL

[rinna11]

Fixes: #20422

This allows AggregateFilter and PrefixFilter to filter by their family similar with IPAddressFilter.
I've tested the following queries manually:

aggregate_v6: aggregate_list(filters: {family: FAMILY_6}) {
    prefix
}
prefixes_v4: prefix_list(filters: {family: FAMILY_4}) {
    prefix
    role {
      name
    }
    vrf {
      name
    }
    vlan {
      vid
    }
}

[jnovinger]

Thanks for the work, @rinna11. The approach looks good and correctly follows the existing pattern.

Please add tests covering the family filter for both AggregateFilter and PrefixFilter, with both FAMILY_4 and FAMILY_6 values to verify the filter returns the correct address family results.

You can add custom test methods to the AggregateTest and PrefixTest classes in ipam/tests/test_api.py. These inherit from APIViewTestCase which provides self.client, self.user, and other helpers. Please mark these tests with @tag('regression'), which you can see elsewhere in the same file. For examples, see the templated tests that are defined in netbox/tests/test_graphql.py.