Upgrade flutter_rust_bridge to v2.11.1

[erdemyerebasmaz]

Hey BDK team,

A dependent crate of flutter_rust_bridge has introduced breaking changes that are causing issues during code generation on older versions. This has been resolved in their latest version, 2.11.1.

Would you mind upgrading flutter_rust_bridge to '>=2.11.1' and publishing a new version of your plugin to pub.dev?

Thanks!

---

Please see: fzyzcjy/flutter_rust_bridge#2793