### 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
target = String();
	target_favorites = false;
	
	if (p_from == files) {
		int pos = files->get_item_at_position(p_point, true);
		if (pos == -1) {
			return;
		}
		String ltarget = files->get_item_metadata(pos);
		target = ltarget.ends_with("/") ? ltarget : current_path.get_base_dir();
		return;
	}
	
	if (p_from == tree) {
		TreeItem *ti = tree->get_item_at_position(p_point);
		int section = tree->get_drop_section_at_position(p_point);
		if (ti) {
			
			if (ti == tree->get_root()->get_first_child() && section >= 0) {
				target_favorites = true;
				return;
			} else if (ti->get_parent() == tree->get_root()->get_first_child()) {
				target_favorites = true;
				return;