oneOf: incorrectly typed as map[string]jx.Raw in 1.2.0, 1.2.1

[germainc]

What version of ogen are you using?

1.2.1

Can this issue be reproduced with the latest version?

Yes

What did you do?

    "EntityName": {
        "oneOf": [
          {
            "$ref": "#/components/schemas/PersonName"
          },
          {
            "$ref": "#/components/schemas/BusinessName"
          }
        ],
        "type": "object",
        "x-schema-id": "entity_name"
    }

What did you expect to see?

// Ref: #/components/schemas/EntityName
type EntityName struct {
	OneOf EntityNameSum
}

What did you see instead?

// Ref: #/components/schemas/EntityName
type EntityName map[string]jx.Raw