In order for TestData.clusterAuthMode to be set, clusterAuthMode must be configured as part of the suite. Since clusterAuthMode is a property of the mongod, jstest.options().clusterMode is never set and always defaults to 'keyFile'. Thus, atuhutil.asCluster should use 'conn' to check for the setting of clusterAuthMode instead of using jstest.options. 

Currently, authutil.asCluster won't work for some tests that require x509 auth, since auth mode defaults to 'keyFile,' and x509 authorization cannot be reached in the code.