Bump tox from 4.14.2 to 4.15.0

Bumps [tox](https://github.com/tox-dev/tox) from 4.14.2 to 4.15.0.
- [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@4.14.2...4.15.0)

---
updated-dependencies:
- dependency-name: tox
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

setup.py

@@ -62,7 +62,7 @@
  # Setup.
  "pre-commit==3.7.0 ; python_version>='3.9'",
  "tox==3.27.1 ; python_version<'3.8'",
- "tox==4.14.2 ; python_version>='3.8'",
+ "tox==4.15.0 ; python_version>='3.8'",
  # Testing framework.
  "pytest==6.1.2 ; python_version<'3.8'",
  "pytest==8.1.1 ; python_version>='3.8'",