### 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 (file_list_display_mode == FILE_LIST_DISPLAY_THUMBNAILS && p_path.get_base_dir() == current_path && searched_string.length() == 0 && file_list_vb->is_visible_in_tree()) {
		for (int i = 0; i < files->get_item_count(); i++) {
			if (files->get_item_metadata(i) == p_path) {
				
				Array udata;
				udata.resize(2);
				udata[0] = i;
				udata[1] = files->get_item_text(i);
				EditorResourcePreview::get_singleton()->queue_resource_preview(p_path, this, "_file_list_thumbnail_done", udata);
				break;
			}
		}
	}
}
void FileSystemDock::_fs_changed() {
	button_hist_prev->set_disabled(history_pos == 0);
	button_hist_next->set_disabled(history_pos == history.size() - 1);
	scanning_vb->hide();
	split_box->show();
	if (tree->is_visible()) {
		_update_tree(get_uncollapsed_paths());
	}
	if (file_list_vb->is_visible()) {
		_update_file_list(true);
	}
	set_process(false);
}
void FileSystemDock::_set_scanning_mode() {