fix(emqx_auth_http_app): Dialyzer warnings

apps/emqx_auth_http/src/emqx_auth_http_app.erl

@@ -36,8 +36,8 @@ start(_StartType, _StartArgs) ->
         ok ->
             {ok, PoolOpts} = application:get_env(?APP, pool_opts),
             {ok, Sup} = emqx_http_client_sup:start_link(?APP, ssl(inet(PoolOpts))),
-            with_env(auth_req, fun load_auth_hook/1),
-            with_env(acl_req,  fun load_acl_hook/1),
+            _ = with_env(auth_req, fun load_auth_hook/1),
+            _ = with_env(acl_req,  fun load_acl_hook/1),
             {ok, Sup};
         {error, Reason} ->
             {error, Reason}
@@ -144,4 +144,4 @@ same_host_and_port([{_, {Host, Port, _}}, {_, {Host, Port, _}}]) ->
 same_host_and_port([{_, {Host, Port, _}}, URL = {_, {Host, Port, _}} | Rest]) ->
     same_host_and_port([URL | Rest]);
 same_host_and_port(_) ->
-    false.
+    false.