Update dependency flutter_lints to v4

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
flutter_lints (source)	dev_dependencies	major	^3.0.2 -> ^4.0.0

---

Release Notes

flutter/packages (flutter_lints)

### [`v4.0.0`](https://togithub.com/flutter/packages/blob/HEAD/packages/flutter_lints/CHANGELOG.md#400) [Compare Source](https://togithub.com/flutter/packages/compare/flutter_lints-v3.0.2...flutter_lints-v4.0.0) - Updates `package:lints` dependency to version 4.0.0, with the following changes: - adds `library_annotations` - adds `no_wildcard_variable_uses` - removes `package_prefixed_library_names` - removes `library_names`

---

Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• [ ] If you want to rebase/retry this PR, check this box

---

This PR has been generated by Mend Renovate. View repository job log here.