WFLY-2354 : Webservice13 tck failures introduced by ejb3 and security change (WFLY-981)

Fixing regression by testing that the Singleton is properly configured for security before adding the interceptor.

Jira : https://issues.jboss.org/browse/WFLY-2354
BZ : https://bugzilla.redhat.com/show_bug.cgi?id=1021543 (acked)

This is the correct version , sorry for the previous PR where i took the wrong block when porting from EAP.