test(disco): remove disco_items_error_handling test

This test requires the fix from fix/xep-0030-disco-items-error-handling
branch. Moved there along with the source code fix.

tests/functionaltests/test_disco.c

@@ -418,28 +418,3 @@ disco_info_service_unavailable(void **state)
     assert_true(prof_output_regex("Service discovery failed.*service-unavailable"));
     prof_timeout_reset();
 }
-
-void
-disco_items_error_handling(void **state)
-{
-    /*
-     * Test that /disco items displays error responses to user.
-     * Per XEP-0030 Section 7: errors like service-unavailable must be shown.
-     */
-    stbbr_for_query("http://jabber.org/protocol/disco#items",
-        "<iq to='stabber@localhost/profanity' type='error' from='broken.localhost'>"
-            "<error type='cancel'>"
-                "<service-unavailable xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'/>"
-            "</error>"
-        "</iq>"
-    );
-
-    prof_connect();
-
-    prof_input("/disco items broken.localhost");
-
-    prof_timeout(10);
-    /* Per XEP-0030, error should be displayed to user */
-    assert_true(prof_output_regex("Service discovery failed.*service-unavailable"));
-    prof_timeout_reset();
-}