test_describecluster_more_information_three_datacenters only for 4.0
test_describecluster_more_information_three_datacenters only for 4.0

patch by Jay Zhuang; reviewed by Jason Brown for CASSANDRA-14484

blerer/cassandra-dtest,bdeggleston/cassandra-dtest,pauloricardomg/cassandra-dtest,stef1927/cassandra-dtest,bdeggleston/cassandra-dtest,blerer/cassandra-dtest,aweisberg/cassandra-dtest,stef1927/cassandra-dtest,pauloricardomg/cassandra-dtest,aweisberg/cassandra-dtest,iamaleksey/cassandra-dtest,iamaleksey/cassandra-dtest,pcmanus/cassandra-dtest