Update flake8-isort requirement from <4.1,>=4.0 to >=4.0,<4.2

Updates the requirements on [flake8-isort](https://github.com/gforcada/flake8-isort) to permit the latest version.
- [Release notes](https://github.com/gforcada/flake8-isort/releases)
- [Changelog](https://github.com/gforcada/flake8-isort/blob/master/CHANGES.rst)
- [Commits](gforcada/flake8-isort@4.0.0...4.1.1)

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

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

requirements/development.txt

@@ -6,6 +6,6 @@ flake8>=3.8,<4.1
 flake8-bugbear>=21.4,<21.5
 flake8-builtins>=1.5,<1.6
 flake8-eradicate>=1.0,<1.2
-flake8-isort>=4.0,<4.1
+flake8-isort>=4.0,<4.2
 pre-commit>=2.13,<2.17
 pytest-cov>=2.11,<3.1