ui: 支持客观题配置

packages/ui-default/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@hydrooj/ui-default",
-  "version": "4.5.10",
+  "version": "4.5.11",
   "author": "undefined <i@undefined.moe>",
   "license": "AGPL-3.0",
   "main": "hydro.js",
@@ -31,7 +31,6 @@
     "babel-loader": "^8.2.2",
     "babel-plugin-lodash": "^3.3.4",
     "babel-plugin-prismjs": "^2.0.1",
-    "base-64": "^1.0.0",
     "chalk": "^4.1.0",
     "classnames": "^2.3.1",
     "clipboard": "^2.0.8",