Incorrect error response when setting too many rules in membership screening

[advaith1]

Description

When setting over 16 (the limit) rules in membership screening, the error response is formatted wrong.

Steps to Reproduce
PATCH https://discord.com/api/v8/guilds/:id/member-verification with

{
    "form_fields": "[{\"field_type\":\"TERMS\",\"label\":\"hello world\",\"values\":[\"test\",\"test\",\"test\",\"test\",\"test\",\"test\",\"test\",\"test\",\"test\",\"test\",\"test\",\"test\",\"test\",\"test\",\"test\",\"test\",\"test\"],\"required\":true}]"
}

Expected Behavior

an error response like this:

{
    "code": 50035,
    "errors": {
        "form_fields": {
            "values": {
                "_errors": [
                    {
                        "code": "BASE_TYPE_MAX_LENGTH",
                        "message": "Must be 16 or fewer in length."
                    }
                ]
            }
        }
    },
    "message": "Invalid Form Body"
}

Current Behavior

this error response, with two _errors arrays:

{
    "code": 50035,
    "errors": {
        "form_fields": {
            "values": {
                "_errors": [
                    {
                        "_errors": [
                            {
                                "code": "BASE_TYPE_MAX_LENGTH",
                                "message": "Must be 16 or fewer in length."
                            }
                        ]
                    }
                ]
            }
        }
    },
    "message": "Invalid Form Body"
}

Screenshots/Videos

Client and System Information

Tested in Postman, first noticed by discord.js not properly handling the error

[night]

This may be fixed as I'm not able to reproduce this issue.