chore: fix dialyzer warning

apps/emqx_machine/src/emqx_machine.app.src

@@ -6,7 +6,7 @@
     {vsn, "0.3.1"},
     {modules, []},
     {registered, []},
-    {applications, [kernel, stdlib, emqx_ctl]},
+    {applications, [kernel, stdlib, emqx_ctl, redbug]},
     {mod, {emqx_machine_app, []}},
     {env, []},
     {licenses, ["Apache-2.0"]},

apps/emqx_machine/src/user_default.erl

@@ -35,6 +35,9 @@
 -export([lock/0, unlock/0]).
 -export([trace/0, t/0, t/1, t/2, t_msg/0, t_msg/1, t_stop/0]).
 
+-dialyzer({nowarn_function, start_trace/3}).
+-dialyzer({no_return, [t/0, t/1, t/2]}).
+
 lock() -> emqx_restricted_shell:lock().
 unlock() -> emqx_restricted_shell:unlock().