Bug: Nullable Subschema (anyOf with null) causes UI exception

[gersmann]

A schema with this top level defiinition:
'anyOf': [{'$ref': '#/$defs/TestModel'}, {'type': 'null'}]

Leads to an UI error, whent he null option is selected.

Initial:

After selecting null option:

The widget should probably replace / reinitialize the form data, if another anyOf option is selected.

Console:

Error: No matching subschema found in 'anyOf' for data '' (type: string)
    T http://localhost:8000/static/django_jsonform/react-json-form.js:1
    <anonymous> http://localhost:8000/static/django_jsonform/react-json-form.js:1
    render http://localhost:8000/static/django_jsonform/react-json-form.js:1
    React 23
[add:12714:25](http://localhost:8000/admin/returns/returnregistration/add/?account=1)
    overrideMethod http://localhost:8000/admin/returns/returnregistration/add/?account=1:12714
    React 25