自主学习下拉框无数据设置为中文显示

src/components/study/SelfDirectedLearning.vue

@@ -22,6 +22,7 @@
                 placeholder=""
                 style="width: 150px"
                 class="custom-select"
+                no-match-text="无匹配数据"
                 @visible-change="handleVisibleChange('course', $event)"
               >
               <template #prefix>
@@ -43,6 +44,7 @@
                 placeholder=""
                 style="width: 150px"
                 class="custom-select"
+                no-match-text="无匹配数据"
                 @visible-change="handleVisibleChange('teacher', $event)"
               >
               <template #prefix>
@@ -64,6 +66,7 @@
                 placeholder=""
                 style="width: 150px"
                 class="custom-select"
+                no-match-text="无匹配数据"
                 @visible-change="handleVisibleChange('assistant', $event)"
               >
               <template #prefix>