Fix org.jboss.test.jacc.test.WebIntegrationUnitTestCase in HEAD

There is privileges related exception that is showing up in HEAD whereas in Branch_4_0, does not show up.

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10:37:07,843 INFO [ENCServlet] InitialContext.env:
10:37:07,843 INFO [ENCServlet] Key: java.naming.factory.initial, value: org.jnp.interfaces.NamingContextFactory
10:37:07,843 INFO [ENCServlet] Key: java.naming.factory.url.pkgs, value: org.jboss.naming:org.jnp.interfaces:org.jboss.naming:org.jnp.interfaces
10:37:07,890 ERROR [[invoker]] Allocate exception for servlet invoker
java.lang.SecurityException: Servlet of class org.apache.catalina.servlets.Invok
erServlet is privileged and cannot be loaded by this web application
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.
java:1114)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:784)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:130)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
at org.jboss.web.tomcat.security.SecurityAssociationValve.invoke(SecurityAssociationValve.java:174)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(Authentica
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Something changed in TC6 as to how web apps can invoke the container servlets?