fix: DictTag text为null时 无法进行toString() 导致系统崩溃

src/components/Table/src/hooks/useRender.ts

@@ -94,7 +94,7 @@ export const useRender = {
    */
   renderDict: (text, type, dictType?) => {
     if (type) {
-      return h(DictTag, { type: type, value: text, dictType: dictType || 'number' })
+      return h(DictTag, { type: type, value: text || '', dictType: dictType || 'number' })
     }
     return ''
   },