### 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
overwrite_dialog->hide();
	_move_operation_confirm(to_move_path, to_move_or_copy, p_overwrite ? OVERWRITE_REPLACE : OVERWRITE_RENAME);
}
Vector<String> FileSystemDock::_check_existing() {
	Vector<String> conflicting_items;
	for (const FileOrFolder &item : to_move) {
		String old_path = item.path.trim_suffix("/");
		String new_path = to_move_path.path_join(old_path.get_file());
		if ((item.is_file && FileAccess::exists(new_path)) || (!item.is_file && DirAccess::exists(new_path))) {
			conflicting_items.push_back(old_path);
		}
	}
	return conflicting_items;
}
void FileSystemDock::_move_dialog_confirm(const String &p_path) {