add TagCacheManager to index

packages/growi-commons/src/index.js

@@ -4,6 +4,7 @@ module.exports = {
   envUtils: require('./util/env-utils'),
   // plugin
   customTagUtils: require('./plugin/util/custom-tag-utils'),
+  TagCacheManager: require('.plugin/service/tag-cache-manager'),
   // service
   LocalStorageManager: require('./service/localstorage-manager'),
 };