chore(deps): update dependency flake8 to v7 (stable) (#2871)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [flake8](https://togithub.com/pycqa/flake8)
([changelog](https://flake8.pycqa.org/en/latest/release-notes/index.html))
| `>=6.0.0,<7` -> `>=6.0.0,<8` |
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|
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|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/pypi/flake8/6.1.0/7.0.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
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|

---

### Release Notes

<details>
<summary>pycqa/flake8 (flake8)</summary>

### [`v7.0.0`](https://togithub.com/pycqa/flake8/compare/6.1.0...7.0.0)

[Compare
Source](https://togithub.com/pycqa/flake8/compare/6.1.0...7.0.0)

</details>

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