build(deps-dev): bump pytest-cov from 2.11.1 to 2.12.1

Bumps [pytest-cov](https://github.com/pytest-dev/pytest-cov) from 2.11.1 to 2.12.1.
- [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@v2.11.1...v2.12.1)

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

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

Author: dependabot[bot]

requirements-dev.txt

@@ -1,10 +1,10 @@
 coverage == 5.5
 freezegun == 1.1.0
-mypy == 0.812
+mypy == 0.910
 pylint == 2.8.2
-pytest == 6.2.3
+pytest == 6.2.4
 pytest-asyncio == 0.15.1
-pytest-cov == 2.11.1
+pytest-cov == 2.12.1
 pytest-random-order == 1.0.4
 responses == 0.13.3
 sqlalchemy-stubs == 0.4