Update dependency retrofit_generator to v3 - autoclosed

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
retrofit_generator (source)	dev_dependencies	major	^2.0.0+1 -> ^3.0.0

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Release Notes

trevorwang/retrofit.dart

### [`v3.0.1+1`](https://togithub.com/trevorwang/retrofit.dart/compare/3.0.1+1...3.0.1+1) [Compare Source](https://togithub.com/trevorwang/retrofit.dart/compare/3.0.1+1...3.0.1+1) ### [`v3.0.1`](https://togithub.com/trevorwang/retrofit.dart/compare/3.0.0+2...3.0.1+1) [Compare Source](https://togithub.com/trevorwang/retrofit.dart/compare/3.0.0+2...3.0.1+1) ### [`v3.0.0+2`](https://togithub.com/trevorwang/retrofit.dart/compare/3.0.0+2...3.0.0+2) [Compare Source](https://togithub.com/trevorwang/retrofit.dart/compare/3.0.0+2...3.0.0+2) ### [`v3.0.0+1`](https://togithub.com/trevorwang/retrofit.dart/releases/3.0.0+1) [Compare Source](https://togithub.com/trevorwang/retrofit.dart/compare/3.0.0+2...3.0.0+2) #### What's Changed - Always keep curly brackets for dynamic paths by [@​woprandi](https://togithub.com/woprandi) in https://github.com/trevorwang/retrofit.dart/pull/416 **Full Changelog**: https://github.com/trevorwang/retrofit.dart/compare/3.0.0...3.0.0+1 ### [`v3.0.0`](https://togithub.com/trevorwang/retrofit.dart/releases/3.0.0) [Compare Source](https://togithub.com/trevorwang/retrofit.dart/compare/2.2.0...3.0.0+2) #### What's Changed - \[wip] Define a new parser annotation for using the Flutter compute function by [@​via-guy](https://togithub.com/via-guy) in https://github.com/trevorwang/retrofit.dart/pull/407 - `FlutterCompute` documentation + v3.0.0 by [@​via-guy](https://togithub.com/via-guy) in https://github.com/trevorwang/retrofit.dart/pull/412 - Use Flutter compute for parsing models by [@​via-guy](https://togithub.com/via-guy) in https://github.com/trevorwang/retrofit.dart/pull/408 **Full Changelog**: https://github.com/trevorwang/retrofit.dart/compare/2.2.0...3.0.0

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Configuration

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