JBTM-2272 fix for 4.17

ISE failure in CDI transactional observer methods with remote EJB call using JTS

NO_TEST
@zhfeng you need something like this: https://github.com/jboss/jboss-el-api_spec/commit/88e00f1d2e901cf6945471c573583fe0f0d8d58d

you need the same on the setContextClassLoader too a bit lower down the class.