### Godot version

v4.1.2.rc1.official [58f0cae4a] and v4.2.dev5.official [e3e2528ba]

### System information

Godot v4.1.2.rc1 - Windows 10.0.19044 - Vulkan (Compatibility) - NVIDIA GeForce GTX 1650 (NVIDIA; 31.0.15.3742) - AMD Ryzen 5 3550H with Radeon Vega Mobile Gfx (8 Threads)

### Issue description

Clearing one of the values of a typed array in the inspector seems to just unreference value and not set it to `<null>`, so the value becomes `<Object#null>`. Array's find function seems to look for the `<null>` value and doesn't accept `<Object#null>`, even if in GDScript `<Object#null>` == `<null>`. So, when calling array.find(null) in the tool script, the function can't find anything. When the project is restarted or you run it, the values that were equal to `<Object#null>` will become `<null>`.
![image](https://github.com/godotengine/godot/assets/118438257/208dbf2c-19ea-4d97-9e46-646662cb5122)

### Steps to reproduce

1. Export a typed array of Resource or any of the types that inherit from it;
2. Set one of the values of a typed array to anything;
3. Clear the value;
4. Use array.find(null) in any of the tool scripts.

### Minimal reproduction project

[ArrayBug.zip](https://github.com/godotengine/godot/files/12789530/ArrayBug.zip)
if (is_read_only()) {
		return false;
	}
	String allowed_type = Variant::get_type_name(subtype);
	
	
	if (subtype == Variant::OBJECT && !subtype_hint_string.is_empty()) {
		allowed_type = subtype_hint_string;
	}
	Dictionary drag_data = p_drag_data;
	if (drag_data.has("type") && String(drag_data["type"]) == "files") {
		Vector<String> files = drag_data["files"];
		for (int i = 0; i < files.size(); i++) {
			String file = files[i];
			String ftype = EditorFileSystem::get_singleton()->get_file_type(file);
			for (int j = 0; j < allowed_type.get_slice_count(","); j++) {
				String at = allowed_type.get_slice(",", j).strip_edges();
				
				if (!ClassDB::is_parent_class(ftype, at)) {
					return false;
				}
			}
		}
		
		return true;
	}
	return false;
}
bool EditorPropertyArray::can_drop_data_fw(const Point2 &p_point, const Variant &p_data, Control *p_from) const {