Update tox requirement from ~=4.15 to ~=4.16

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@4.15.0...4.16.0)

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

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

dev_requirements.txt

@@ -2,4 +2,4 @@ dbt-tests-adapter~=1.8.0
 mypy==1.10.0  # patch updates have historically introduced breaking changes
 pre-commit~=3.7
 pytest~=8.2
-tox~=4.15
+tox~=4.16