Bump coverage from 7.6.7 to 7.6.8

Bumps [coverage](https://github.com/nedbat/coveragepy) from 7.6.7 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@7.6.7...7.6.8)

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

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

pyproject.toml

@@ -32,7 +32,7 @@ dependencies = [
 [project.optional-dependencies]
 dev = [
     "async-timeout==4.0.3",
-    "coverage==7.6.7",
+    "coverage==7.6.8",
     "flit==3.10.1",
 ]