Update flake8 requirement from 6.1.0 to 7.0.0 (#411)

Updates the requirements on [flake8](https://github.com/pycqa/flake8) to permit the latest version.
- [Commits](PyCQA/flake8@6.1.0...7.0.0)

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

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

pyproject.toml

@@ -28,7 +28,7 @@ qiskit = "0.45.1"
 
 [tool.poetry.dev-dependencies]
 distlib = "0.3.8"
-flake8 = "6.1.0"
+flake8 = "7.0.0"
 flake8-docstrings = "1.7.0"
 ipython = "8.19.0"
 isort = "5.13.2"