### 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
String fpath = current_path;
	if (!fpath.ends_with("/")) {
		fpath = fpath.get_base_dir();
	}
	String type_name = new_resource_dialog->get_selected_type();
	if (type_name == "Shader") {
		make_shader_dialog->config(fpath.path_join("new_shader"), false, false, 0);
		make_shader_dialog->popup_centered();
		return;
	} else if (type_name == "VisualShader") {
		make_shader_dialog->config(fpath.path_join("new_shader"), false, false, 1);
		make_shader_dialog->popup_centered();
		return;
	} else if (type_name == "ShaderInclude") {
		make_shader_dialog->config(fpath.path_join("new_shader_include"), false, false, 2);
		make_shader_dialog->popup_centered();
		return;
	}
	Variant c = new_resource_dialog->instantiate_selected();
	ERR_FAIL_COND(!c);
	Resource *r = Object::cast_to<Resource>(c);
	ERR_FAIL_COND(!r);
	PackedScene *scene = Object::cast_to<PackedScene>(r);
	if (scene) {
		Node *node = memnew(Node);