Bump flake8 from 5.0.4 to 7.0.0 in /requirements

Bumps [flake8](https://github.com/pycqa/flake8) from 5.0.4 to 7.0.0.
- [Commits](PyCQA/flake8@5.0.4...7.0.0)

---
updated-dependencies:
- dependency-name: flake8
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

requirements/lint.txt

@@ -4,7 +4,7 @@ attrs==23.2.0
 black==23.12.1
 click==8.1.7
 isort==5.13.2
-flake8==5.0.4
+flake8==7.0.0
 flake8-bugbear==23.12.2
 flake8-future-import==0.4.7
 flake8-no-u-prefixed-strings==0.2