Fix test configuration object names for 2.2

The 2.2 object names are converted to hyphen separated forms to make them
REST API conforming.

maxscale-system-test/rw_select_insert.cpp

@@ -132,7 +132,7 @@ int main(int argc, char *argv[])
     Test->tprintf("Connecting to RWSplit %s\n", Test->maxscale_IP);
     Test->connect_rwsplit();
 
-    Test->execute_maxadmin_command((char *) "shutdown monitor \"MySQL Monitor\"");
+    Test->execute_maxadmin_command((char *) "shutdown monitor MySQL-Monitor");
 
     get_global_status_allnodes(&selects[0], &inserts[0], Test->repl, silent);