pip(deps-dev): update isort requirement in /backend (#84)

Updates the requirements on [isort](https://github.com/PyCQA/isort) to permit the latest version.
- [Release notes](https://github.com/PyCQA/isort/releases)
- [Changelog](https://github.com/PyCQA/isort/blob/main/CHANGELOG.md)
- [Commits](PyCQA/isort@5.9.3...6.0.1)

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

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: garotm <gmconklin@gmail.com>

Author: dependabot[bot]

backend/pyproject.toml

@@ -16,8 +16,8 @@ python-jose = {extras = ["cryptography"], version = "^3.3.0"}
 [tool.poetry.dev-dependencies]
 pytest = "^8.3.4"
 pytest-cov = "^6.0.0"
+isort = "^6.0.1"
 black = "^25.1"
-isort = "^5.9.3"
 flake8 = "^7.1.1"
 
 [build-system]