build(deps-dev): bump pytest-cov from 2.12.1 to 3.0.0

Bumps [pytest-cov](https://github.com/pytest-dev/pytest-cov) from 2.12.1 to 3.0.0.
- [Release notes](https://github.com/pytest-dev/pytest-cov/releases)
- [Changelog](https://github.com/pytest-dev/pytest-cov/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest-cov@v2.12.1...v3.0.0)

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

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

Author: dependabot[bot]

requirements-dev.txt

@@ -4,7 +4,7 @@ mypy == 0.910
 pylint == 2.11.1
 pytest == 6.2.5
 pytest-asyncio == 0.15.1
-pytest-cov == 2.12.1
+pytest-cov == 3.0.0
 pytest-random-order == 1.0.4
 responses == 0.14.0
 types-requests == 2.25.6