超过切屏次数触发交卷时，关闭有可能点击了“交卷”按钮时弹出的确认交卷的弹框，防止二次触发交卷接口报错

src/features/OnlineExam/ExamEnd/SubmitPaper.vue

@@ -43,7 +43,10 @@ async function realSubmitPaper() {
   });
 }
 
-onMounted(() => realSubmitPaper());
+onMounted(() => {
+  $dialog.destroyAll();
+  return realSubmitPaper();
+});
 
 onUnmounted(() => {
   store.decreaseGlobalMaskCount("SubmitPaper");