Describe the bug
When I'm using JsonSetter.Value.forValueNulls(Nulls.AS_EMPTY, Nulls.AS_EMPTY) for nullable value with type java.lang.Object in a Map, I still getting the null in the deserialized object. I think that problem is that com.fasterxml.jackson.databind.deser.std.UntypedObjectDeserializer.Vanilla doesn't override com.fasterxml.jackson.databind.JsonDeserializer#getEmptyValue(com.fasterxml.jackson.databind.DeserializationContext). I think that the deserializer for object should return empty object in the getEmptyValue method.

Version information
2.13.2.2

To Reproduce
If you have a way to reproduce this with:

1. Create a JSON, like this:

{
  "a": {
    "first": "second",
    "third": null
  }
}

2. Create this class to deserialize with:

import java.util.Map;

public class Scratch {
    private Map<String, Object> a;

    public Map<String, Object> getA() {
        return a;
    }

    public void setA(Map<String, Object> a) {
        this.a = a;
    }
}

3. Create the ObjectMapper and override nullable behavior:

        final ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.configOverride(Map.class).setSetterInfo(JsonSetter.Value.forValueNulls(Nulls.AS_EMPTY, Nulls.AS_EMPTY));

4. Deserialize this JSON:

        String json = "...";
        final Scratch scratch = objectMapper.readValue(json, Scratch.class);

5. Verify that in the a object we got a null in the third key:

        final Object third = scratch.getA().get("third");
        assert third != null; // fails

Expected behavior
I'm expecting that the empty value of the java.lang.Object is a new Object instance.