chore: update admin layout title to '分布式OJ系统'

src/layout/AdminLayout.vue

@@ -4,7 +4,7 @@ import {computed, type ComputedRef, ref} from "vue";
 import type {RouteRecordRaw} from "vue-router";
 import router, {adminRoutes} from "../router";
 
-const title = ref<string>("标题");
+const title = ref<string>("分布式OJ系统");
 const loginUserStore = useLoginUserStore()
 const login = computed(()=>loginUserStore.loginUser.isLogin)
 const loginHandler = () => {