Update pubspec.yaml (#697)

CHANGELOG.md

+#5.5.0
+* 更新鸿蒙sdk，支持openBusinessView,onWXLaunchFromWX
+* 
 # 5.4.2
 * 更新一下API文档
 

pubspec.yaml

 name: fluwx
 description: The capability of implementing WeChat SDKs in Flutter. With Fluwx, developers can use WeChatSDK easily, such as sharing, payment, lanuch mini program and etc.
-version: 5.4.2
+version: 5.5.0
 homepage: https://github.com/OpenFlutter/fluwx
 
 environment: