[RESTEASY-1995] remove unused imports from JaxrsWithSpringMVCTest

[marekkopecky]

testsuite/integration-tests-spring/deployment module can't be built with unused import of javax.xml.ws.WebServicePermission on JDK11:

11:32:52 [ERROR] COMPILATION ERROR : 
11:32:52 [INFO] -------------------------------------------------------------
11:32:52 [ERROR] /home/hudson/hudson_workspace/workspace/eap-7.x-resteasy-functional-ts-rhel/64f1522b/resteasy/testsuite/integration-tests-spring/deployment/src/test/java/org/jboss/resteasy/test/spring/deployment/JaxrsWithSpringMVCTest.java:[6,20] package javax.xml.ws does not exist

JDK11 test run with this fix is linked on jira

Jira: https://issues.jboss.org/browse/RESTEASY-1995
3.6 PR: #1661
master PR: merged a few time ago: #1611