build(deps-dev): update flake8 requirement from <8,>=5.0.4 to >=7.3.0,<8

Updates the requirements on [flake8](https://github.com/pycqa/flake8) to permit the latest version.
- [Commits](PyCQA/flake8@5.0.4...7.3.0)

---
updated-dependencies:
- dependency-name: flake8
  dependency-version: 7.3.0
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

requirements/dev-tools.txt

@@ -1,3 +1,3 @@
 black
-flake8>=5.0.4, <8;
+flake8>=7.3.0, <8;
 mypy>=1.11.1, <2