fix a bug which cannot include teacher in the params

frontend/src/views/account/Account.vue

@@ -181,7 +181,6 @@
           page: 1,
           ordering: '-last_login',
           role: '',
-          teacher: this.$store.getters.role === 'TEACHER' ? this.$store.getters.userid : '',
         },
         state: {
           loading: false,
@@ -202,6 +201,9 @@
     methods: {
       getData () {
         this.state.loading = true
+        if (this.$store.getters.role === 'TEACHER') {
+          this.params.teacher = this.$store.getters.userid
+        }
         api.getUserList(this.params)
           .then(data => {
             this.userList = data.results