remove random_string tests
remove random_string tests

Signed-off-by: Tyler Pickett <1d7399073f785129b42f375de87dfa551441ffbc@gmail.com>
infoman/rubycas-server,identification-io/rubycas-server,identification-io/rubycas-server,geo767/rubycas-server,jay3126/ruby_cas_server,geo767/rubycas-server,adamdruppe/rubycas-server,geo767/rubycas-server,infoman/rubycas-server,infoman/rubycas-server,adamdruppe/rubycas-server,adamdruppe/rubycas-server,jay3126/ruby_cas_server,rubycas/rubycas-server,rubycas/rubycas-server,identification-io/rubycas-server,rubycas/rubycas-server