chore: remove ignored files from tracking

frontend/node_modules/css-tree/lib/utils/clone.js

@@ -1,21 +0,0 @@
-import { List } from './List.js';
-
-export function clone(node) {
-    const result = {};
-
-    for (const key in node) {
-        let value = node[key];
-
-        if (value) {
-            if (Array.isArray(value) || value instanceof List) {
-                value = value.map(clone);
-            } else if (value.constructor === Object) {
-                value = clone(value);
-            }
-        }
-
-        result[key] = value;
-    }
-
-    return result;
-}