Incorrect behaviour of nested JSON_OBJECT functions

[evyalyy]

Following query produces incorrect result:

> select JSON_OBJECT('equipments', JSON_OBJECT('i', 1));
+------------------------------------------------+
| JSON_OBJECT('equipments', JSON_OBJECT('i', 1)) |
+------------------------------------------------+
| {"equipments":{"Val":{"i":1}}}                 |
+------------------------------------------------+

When expected result should be

{"equipments": {"i":1}}

[jennifersp]

fixed with dolthub/go-mysql-server#741