build(deps-dev): update coverage requirement from >=7.15.2 to >=7.15.4

Updates the requirements on [coverage](https://github.com/coveragepy/coveragepy) to permit the latest version.
- [Release notes](https://github.com/coveragepy/coveragepy/releases)
- [Changelog](https://github.com/coveragepy/coveragepy/blob/main/CHANGES.rst)
- [Commits](coveragepy/coveragepy@7.15.2...7.15.4)

---
updated-dependencies:
- dependency-name: coverage
  dependency-version: 7.15.4
  dependency-type: direct:development
...

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

Author: dependabot[bot]

requirements-dev.txt

@@ -8,4 +8,4 @@ pre-commit >= 4.6.1
 empty-files >= 0.0.9
 robotframework-tidy >=4.18.0
 ruff >= 0.16.1
-coverage >= 7.15.2
+coverage >= 7.15.4