Bump flake8 from 4.0.1 to 5.0.4 in /.github/workflows

Bumps [flake8](https://github.com/pycqa/flake8) from 4.0.1 to 5.0.4.
- [Release notes](https://github.com/pycqa/flake8/releases)
- [Commits](PyCQA/flake8@4.0.1...5.0.4)

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

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

.github/workflows/constraints.txt

@@ -1,5 +1,5 @@
 pip==22.0.4
 pre-commit==2.20.0
 black==22.3.0
-flake8==4.0.1
+flake8==5.0.4
 reorder-python-imports==3.8.2