Update dependency flutter_lints to v2

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
flutter_lints	dev_dependencies	major	^1.0.0 -> ^2.0.0

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Release Notes

flutter/packages

### [`v2.0.1`](https://togithub.com/flutter/packages/compare/flutter_lints-v2.0.0...flutter_lints-v2.0.1) [Compare Source](https://togithub.com/flutter/packages/compare/flutter_lints-v2.0.0...flutter_lints-v2.0.1) ### [`v2.0.0`](https://togithub.com/flutter/packages/compare/flutter_lints-v1.0.4...flutter_lints-v2.0.0) [Compare Source](https://togithub.com/flutter/packages/compare/flutter_lints-v1.0.4...flutter_lints-v2.0.0)

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Configuration

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