fix:修复学生选课显示bug

src/views/CorrectPage/CoursePage.vue

@@ -93,7 +93,7 @@
     studentId:null,
     courseName:null,
     semester:null,
-    teacherPid:store.user.pid
+    teacherPid:null
   })
 
   let courseName = ref('')

src/views/CoursePage/CoursePage.vue

@@ -178,7 +178,7 @@
   const query = reactive<CourseQuery>({
     courseId:0,
     teacherId:store.user.id,
-    teacherPid:Number(store.user.pid),
+    teacherPid:null,
     studentId:0,
     courseName:"",
     semester:"",
@@ -226,6 +226,7 @@
       Object.assign(query, {
         courseId: null,
         teacherId: null,
+        teacherPid:null,
         studentId: store.user.id,
         courseName: courseName.value,
         semester: null,