Increase dependency version of reactive_pin_code_fields

[perthcpe23]

Please upgrade dependency pin_code_fields from 7.4.0 to 8.0.1

Currently reactive_pin_code_fields rely on pin_code_fields: ^7.4.0 and pin_code_fields: ^7.4.0 is not supported by the latest version of Flutter SDK (v3.24.3) with an error

../../.pub-cache/hosted/pub.dev/pin_code_fields-7.4.0/lib/src/pin_code_fields.dart:669:56:
Error: The getter 'button' isn't defined for the class 'TextTheme'.

The latest version of pin_code_fields: ^8.0.1 works with Flutter SDK (v3.24.3)

[vasilich6107]

Hey @perthcpe23
It would be nice if you could make a PR