bump to 5.2.2

CHANGELOG.md

+# 5.2.2
+* Fix #659，优化iOS脚本，使其更加友好
+
 # 5.2.1
 * Merge #658
 

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: 5.2.1
+version: 5.2.2
 homepage: https://github.com/OpenFlutter/fluwx
 
 environment: