### 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 (resource_type == "PackedScene") {
			bool is_imported = false;
			{
				List<String> importer_exts;
				ResourceImporterScene::get_scene_singleton()->get_recognized_extensions(&importer_exts);
				String extension = fpath.get_extension();
				for (const String &E : importer_exts) {
					if (extension.nocasecmp_to(E) == 0) {
						is_imported = true;
						break;
					}
				}
			}
			if (is_imported) {
				ResourceImporterScene::get_scene_singleton()->show_advanced_options(fpath);
			} else {
				EditorNode::get_singleton()->open_request(fpath);
			}
		} else if (resource_type == "AnimationLibrary") {
			bool is_imported = false;
			{
				List<String> importer_exts;
				ResourceImporterScene::get_animation_singleton()->get_recognized_extensions(&importer_exts);
				String extension = fpath.get_extension();
				for (const String &E : importer_exts) {
					if (extension.nocasecmp_to(E) == 0) {
						is_imported = true;
						break;
					}
				}