[DEPENDABOT]: Bump coverage from 5.3 to 7.2.2

Bumps [coverage](https://github.com/nedbat/coveragepy) from 5.3 to 7.2.2.
- [Release notes](https://github.com/nedbat/coveragepy/releases)
- [Changelog](https://github.com/nedbat/coveragepy/blob/master/CHANGES.rst)
- [Commits](nedbat/coveragepy@coverage-5.3...7.2.2)

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

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

requirements_dev.txt

@@ -3,7 +3,7 @@ wheel==0.35.1
 watchdog==0.10.3
 flake8==3.8.4
 tox==3.20.1
-coverage==5.3
+coverage==7.2.2
 Sphinx==3.3.0
 sphinx-automodapi==0.13
 twine==3.2.0