ui: add hustoj to allowed checker_type list

packages/hydrojudge/src/checkers.ts

@@ -1,5 +1,4 @@
 /* eslint-disable no-template-curly-in-string */
-import fs from 'fs-extra';
 import * as STATUS from './status';
 import { parse } from './testlib';
 import { run } from './sandbox';