Update dependency flake8 to v7.3.0 (#417)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [flake8](https://redirect.github.com/pycqa/flake8)
([changelog](https://flake8.pycqa.org/en/latest/release-notes/index.html))
| `==7.2.0` -> `==7.3.0` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/flake8/7.3.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/pypi/flake8/7.3.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/pypi/flake8/7.2.0/7.3.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/flake8/7.2.0/7.3.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

### Release Notes

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

###
[`v7.3.0`](https://redirect.github.com/pycqa/flake8/compare/7.2.0...7.3.0)

[Compare
Source](https://redirect.github.com/pycqa/flake8/compare/7.2.0...7.3.0)

</details>

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Author: lettuce-bot[bot]

pyproject.toml

@@ -22,7 +22,7 @@ dist = [
 style = [
   "autoflake==2.3.1",
   "black==25.1.0",
-  "flake8==7.2.0",
+  "flake8==7.3.0",
   "flake8-isort==6.1.2",
   "flake8-print==5.0.0",
   "flake8-pyproject==1.2.3",