fix: force proper calling decode to return proplist

apps/emqx_utils/test/props/prop_emqx_utils_json.erl

@@ -66,7 +66,7 @@ prop_object_proplist_to_proplist() ->
         begin
             {ok, J} = safe_encode(T),
             {ok, T} = safe_decode(J),
-            T = decode(encode(T)),
+            T = decode(encode(T), []),
             true
         end
     ).
@@ -108,7 +108,7 @@ prop_object_map_to_proplist() ->
             T = to_list(T0),
             {ok, J} = safe_encode(T0),
             {ok, T} = safe_decode(J),
-            T = decode(encode(T0)),
+            T = decode(encode(T0), []),
             true
         end
     ).