TCK: idle timout connection close behavior

**Challenged tests**
com.sun.ts.tests.websocket.spec.application.closing.WSCClientIT.connectionHasBeenClosedWithStatus1006AfterTimeoutTest

**TCK Version**
HEAD (likely equivalent of 2.2)

**Description**
Test expects after a timeout we get a 1006 NO_CLOSE code, but in Eclipse Jetty we send 1001 GOING_AWAY on network for idle timeout, which is what the Autobahn Websocket Test Suite expects.

**Additional context**
The TCK shouldn't be dictating websocket protocol behaviors, that's for other testing suites to do.
The TCK should be following websocket protocol behavior, and should allow for any of the legitimate close status codes for an idle timeout.

Start with the challenged test com.sun.ts.tests.websocket.spec.application.closing.WSCClientIT.connectionHasBeenClosedWithStatus1006AfterTimeoutTest and review its idle-timeout assertion. Compare the TCK expectation with the stated Jetty and Autobahn behavior, then adjust the test so legitimate idle-timeout close statuses are accepted. Run the challenged test to verify the updated behavior.

Written by the indexing model from the issue text.