JSONField uses dict schema but can be any json primitive

[Kangaroux]

Describe the bug
When using a JSONField in the serializer, the generated schema is for an object. However, DRF describes it as being any json primitive: strings, numbers, booleans, etc. The current implementation seems more appropriate for DictField, not JSONField

To Reproduce

from rest_framework import serializers

class MySerializer(serializers.Serializer):
  json_field = serializers.JSONField()

Expected behavior
The generated type should be OpenApiTypes.ANY.

[tfranzel]

excellent point, a string or number would be possible too.