Update diagnose.test.js

Author: Beakerboy

test/diagnose.test.js

@@ -1,3 +1,7 @@
+/**
+ * @jest-environment jsdom
+ */
+
 import { Shape, Mesh } from 'three';
 import { TextEncoder } from 'node:util';
 import {expect, test, beforeEach, describe} from '@jest/globals';