Update colorlog requirement from ~=6.7 to ~=6.8

Updates the requirements on [colorlog](https://github.com/borntyping/python-colorlog) to permit the latest version.
- [Release notes](https://github.com/borntyping/python-colorlog/releases)
- [Commits](borntyping/python-colorlog@v6.7.0...v6.8.2)

---
updated-dependencies:
- dependency-name: colorlog
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

requirements-test.txt

@@ -1,7 +1,7 @@
 -r requirements.txt
 async-timeout
 asynctest~=0.13
-colorlog~=6.7
+colorlog~=6.8
 flake8~=7.0
 flake8-docstrings~=1.7
 mypy==1.8.0