### Godot version

v4.1.rc2.official [46424488e]

### System information

Godot v4.1.rc2 - Linux Mint 20 (Ulyana) - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 2060 SUPER (nvidia; 515.105.01) - Intel(R) Core(TM) i7-6700K CPU @ 4.00GHz (8 Threads)

### Issue description

Dragging and dropping a file to a new position inside its current folder, or onto the icon for its current folder - when that folder is the project root folder :res// - will be treated as though you were dropping a different file with the same name.

Expectation: for nothing to happen.

Also tried it in 4.0.3 and 4.1-dev3, where it behaves as expected.

https://github.com/godotengine/godot/assets/64640811/90de1120-dd92-41b8-b202-db77c343103a

### Steps to reproduce

1. New or existing project.
2. Click and drag a file in :res// in FileSystem dock.
3. Drop the file back into :res//.
4. Be prompted to overwrite or rename.

### Minimal reproduction project

N/A
if (drag_data.has("type") && String(drag_data["type"]) == "resource") {
		
		String to_dir;
		bool favorite;
		_get_drag_target_folder(to_dir, favorite, p_point, p_from);
		return !to_dir.is_empty();
	}
	if (drag_data.has("type") && (String(drag_data["type"]) == "files" || String(drag_data["type"]) == "files_and_dirs")) {
		
		String to_dir;
		bool favorite;
		_get_drag_target_folder(to_dir, favorite, p_point, p_from);
		if (favorite) {
			return true;
		}
		if (to_dir.is_empty()) {
			return false;
		}
		
		
		to_dir = to_dir.ends_with("/") ? to_dir : (to_dir + "/");
		Vector<String> fnames = drag_data["files"];
		for (int i = 0; i < fnames.size(); ++i) {
			if (fnames[i].ends_with("/") && to_dir.begins_with(fnames[i])) {
				return false;
			}
		}
		return true;
	}
	if (drag_data.has("type") && String(drag_data["type"]) == "nodes") {