fix(test): Increase the delay time

test/emqx_mqtt_SUITE.erl

@@ -92,7 +92,7 @@ message_expiry_interval_exipred(ClientA, QoS) ->
     ct:pal("~p ~p", [?FUNCTION_NAME, QoS]),
     %% publish to t/a and waiting for the message expired
     emqtt:publish(ClientA, <<"t/a">>, #{'Message-Expiry-Interval' => 1}, <<"this will be purged in 1s">>, [{qos, QoS}]),
-    ct:sleep(1500),
+    ct:sleep(2000),
 
     %% resume the session for client-b
     {ok, ClientB1} = emqtt:start_link([{proto_ver,v5},