Remove extra separator

Removes an extra separator when Scene Tree Editing is disabled. Discussed in #48518

(cherry picked from commit e168baf433fee964d103693e227cce7f27b8905e)

editor/scene_tree_dock.cpp

@@ -2647,7 +2647,7 @@ void SceneTreeDock::_tree_rmb(const Vector2 &p_menu_pos) {
 			}
 		}
 
-		if (add_separator) {
+		if (add_separator && profile_allow_editing) {
 			menu->add_separator();
 		}
 	}