Update flake8 requirement from ~=3.7 to >=3.7,<8.0

Updates the requirements on [flake8](https://github.com/pycqa/flake8) to permit the latest version.
- [Commits](PyCQA/flake8@3.7.0...7.1.1)

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

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

setup.py

@@ -117,7 +117,7 @@
             "factory-boy>=2.12,<4.0",
             "livereload~=2.5",
             # Lint and code style
-            "flake8~=3.7",
+            "flake8>=3.7,<8.0",
             "flake8-blind-except~=0.1",
             "flake8-debugger>=3.1,<5.0",
             "flake8-docstrings~=1.3",