fix(cubejs-playground): remove less file import (#6537)

Author: tenphi

packages/cubejs-playground/src/playground/index.less

@@ -1,4 +1,5 @@
-@import '../../node_modules/antd/dist/antd.less';
+/* That was used to generate a css asset. No need to use it anymore. */
+@import '../../../../node_modules/antd/dist/antd.less';
 @import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;700&display=swap&css');
 
 .ant-tabs-dropdown-menu-item {

packages/cubejs-playground/src/playground/index.ts

@@ -1,5 +1,3 @@
-import './index.less';
-
 export * from '../cloud';
 export * from './components/QueryBuilder';
 export * from '../hooks';