chore(deps-dev): update tox requirement from ~=4.14 to ~=4.15 (#982)

Updates the requirements on [tox](https://github.com/tox-dev/tox) to permit the latest version.
- [Release notes](https://github.com/tox-dev/tox/releases)
- [Changelog](https://github.com/tox-dev/tox/blob/main/docs/changelog.rst)
- [Commits](tox-dev/tox@4.14.0...4.15.0)

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

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

Pipfile

@@ -15,7 +15,7 @@ pylint-quotes = "~=0.2.3"
 pytest = "~=8.2"
 pytest-cov = "~=4.1"
 python-dateutil = "~=2.9"
-tox = "~=4.14"
+tox = "~=4.15"
 types-python-dateutil = "~=2.9"
 
 [packages]