Merge pull request #470 from reown-com/fix-flutter-link

Docs Update: Updating Flutter releases URL

Author: rohit-710

walletkit/upgrade/staying-up-to-date.mdx

@@ -31,4 +31,4 @@ Monitor JavaScript and React Native package updates:
 
 ### Flutter
 Check the latest Flutter releases for Flutter development:
-- [Reown Flutter Releases](https://github.com/reown-com/reown_flutter/releases)
+- [Reown WalletKitFlutter Releases](https://pub.dev/packages/reown_walletkit)