Add tests for bp_make_spam/ham_user and make_spam/ham_user filters.

Filters names were originally assigned to a passed in variable but
they were separated out for documentation purposes.

See #5944.


git-svn-id: https://buddypress.svn.wordpress.org/trunk@9233 cdf35c40-ae34-48e0-9cc9-0c9da1808c22