### Godot version

4.0 Beta10

### System information

Ubuntu 22.04 (Tuxedo OS)

### Issue description

After importing an *.obj file as a scene, if you click on the mesh in the import settings Godot crashes.

![Screenshot from 2022-12-24 14-38-23](https://user-images.githubusercontent.com/25522325/209452619-3c0ed61b-deaa-4fb6-8ff5-5aa11ff4ed33.png)

I the above screenshot, clicking in the circled area will crash Godot.

### Steps to reproduce

Import .obj file into a project.
Select the file.
Go to import setting.
Change OBJ As Mesh to Scene.
Click Reimport.
Click Save Scenes, Re-Import, and Restart.
Once restarted, open the advanced import settings on the object.
Click the are circled in the description, or in the meshes tab.

### Minimal reproduction project

N/A

Specifically, I lack the distribution rights of the .obj files I am using.  Any .obj file should do, this happened to me on at least 4 different .obj files.
ERR_FAIL_COND_V(v.size() != 2, ERR_INVALID_DATA);
			float d = v[1].to_float();
			Color c = current->get_albedo();
			c.a = d;
			current->set_albedo(c);
			if (c.a < 0.99) {
				current->set_transparency(StandardMaterial3D::TRANSPARENCY_ALPHA);
			}
		} else if (l.begins_with("Tr ")) {
			
			ERR_FAIL_COND_V(current.is_null(), ERR_FILE_CORRUPT);
			Vector<String> v = l.split(" ", false);
			ERR_FAIL_COND_V(v.size() != 2, ERR_INVALID_DATA);
			float d = v[1].to_float();
			Color c = current->get_albedo();
			c.a = 1.0 - d;
			current->set_albedo(c);
			if (c.a < 0.99) {
				current->set_transparency(StandardMaterial3D::TRANSPARENCY_ALPHA);
			}
		} else if (l.begins_with("map_Ka ")) {
			
			WARN_PRINT("OBJ: Ambient light texture for material '" + current_name + "' is ignored in PBR");
		} else if (l.begins_with("map_Kd ")) {
			
			ERR_FAIL_COND_V(current.is_null(), ERR_FILE_CORRUPT);
			String p = l.replace("map_Kd", "").replace("\\", "/").strip_edges();
			String path;
			if (p.is_absolute_path()) {
				path = p;