Bump pytest-cov from 5.0.0 to 6.0.0 in /server

Bumps [pytest-cov](https://github.com/pytest-dev/pytest-cov) from 5.0.0 to 6.0.0.
- [Changelog](https://github.com/pytest-dev/pytest-cov/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest-cov@v5.0.0...v6.0.0)

---
updated-dependencies:
- dependency-name: pytest-cov
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

server/dev-requirements.txt

@@ -4,7 +4,7 @@ flake8
 sphinx
 sphinx-autobuild
 pytest==8.3.3
-pytest-cov==5.0.0
+pytest-cov==6.0.0
 pytest-mock==3.14.0
 responses>=0.10.6,<0.26
 httmock