vjudge: poj: ensure login before submission

packages/vjudge/package.json

@@ -1,6 +1,6 @@
 {
     "name": "@hydrooj/vjudge",
-    "version": "1.4.2",
+    "version": "1.4.3",
     "description": "Submit problems to remote oj",
     "main": "package.json",
     "repository": "https://github.com/hydro-dev/Hydro.git",

packages/vjudge/src/providers/poj.ts

@@ -200,6 +200,7 @@ export default class POJProvider implements IBasicProvider {
     }
 
     async submitProblem(id: string, lang: string, code: string, info) {
+        await this.ensureLogin();
         const language = lang.includes('poj.') ? lang.split('poj.')[1] : '0';
         const comment = setting.langs[lang].comment;
         if (comment) {