build(deps): bump coverage from 7.5.1 to 7.6.8

Bumps [coverage](https://github.com/nedbat/coveragepy) from 7.5.1 to 7.6.8.
- [Release notes](https://github.com/nedbat/coveragepy/releases)
- [Changelog](https://github.com/nedbat/coveragepy/blob/master/CHANGES.rst)
- [Commits](nedbat/coveragepy@7.5.1...7.6.8)

---
updated-dependencies:
- dependency-name: coverage
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

requirements.txt

@@ -150,7 +150,7 @@ docker==7.0.0
 invoke==2.2.0
 
 # tests
-coverage==7.5.1
+coverage==7.6.8
 requests-toolbelt==1.0.0
 flake8==7.0.0
 black==24.4.2