fix(appup): delete module load from app restart instruction group

apps/emqx_stomp/src/emqx_stomp.appup.src

@@ -2,11 +2,9 @@
 {VSN,
   [{"4.3.1",[{load_module,emqx_stomp_connection,brutal_purge,soft_purge,[]}]},
    {"4.3.0",
-    [{load_module,emqx_stomp_connection,brutal_purge,soft_purge,[]},
-     {restart_application,emqx_stomp}]},
+    [{restart_application,emqx_stomp}]},
    {<<".*">>,[]}],
   [{"4.3.1",[{load_module,emqx_stomp_connection,brutal_purge,soft_purge,[]}]},
    {"4.3.0",
-    [{load_module,emqx_stomp_connection,brutal_purge,soft_purge,[]},
-     {restart_application,emqx_stomp}]},
+    [{restart_application,emqx_stomp}]},
    {<<".*">>,[]}]}.