mysql_upgrade fails to load type_mysql_json due to insufficient maturity level

When mysql_upgrade encounters MySQL JSON type, it attempts to load type_mysql_json. In reality it cannot do so, because the plugin is Alpha, and the default allowed plugin maturity level for GA releases is gamma:

installing plugin for MYSQL_JSON data type

ERROR 1126 (HY000) at line 1: Can't open shared library 'type_mysql_json.so' (errno: 1, Loading of alpha plugin MYSQL_JSON is prohibited by --plugin-maturity=gamma)

It can be especially problematic for Debian package installation, as it runs mysql_upgrade automatically.