fix: 国际化问题

frontend/src/components/canvas/components/Editor/Preview.vue

 <template>
   <div id="canvasInfo" :style="customStyle" class="bg">
     <el-row v-if="componentDataShow.length===0" style="height: 100%;" class="custom-position">
-      <!-- {{ $t('panel.panel_null') }} -->
+      {{ $t('panel.panelNull') }}
     </el-row>
     <ComponentWrapper
       v-for="(item, index) in componentDataInfo"

frontend/src/lang/en.js

@@ -887,7 +887,7 @@ export default {
     insert_picture: 'Insert Picture',
     redo: 'Redo',
     undo: 'Undo',
-    panel_null: 'This is a Empty Panel，You Can Edit and Enrich It'
+    panelNull: 'This is a Empty Panel，You Can Edit and Enrich It'
   },
   plugin: {
     local_install: 'Local installation',

frontend/src/lang/tw.js

@@ -886,7 +886,7 @@ export default {
     insert_picture: '插入圖片',
     redo: '重做',
     undo: '撤銷',
-    panel_null: '这是个空的儀表盤，可以通过编辑来丰富内容'
+    panelNull: '这是个空的儀表盤，可以通过编辑来丰富内容'
   },
   plugin: {
     local_install: '本地安裝',

frontend/src/lang/zh.js

@@ -888,7 +888,7 @@ export default {
     insert_picture: '插入图片',
     redo: '重做',
     undo: '撤销',
-    panel_null: '这是个空的仪表板，可以通过编辑来丰富内容'
+    panelNull: '这是个空的仪表板，可以通过编辑来丰富内容'
   },
   plugin: {
     local_install: '本地安装',