Bump pytest-cov from 2.11.1 to 2.12.0 in /testing/plugins_integration

Bumps [pytest-cov](https://github.com/pytest-dev/pytest-cov) from 2.11.1 to 2.12.0.
- [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@v2.11.1...v2.12.0)

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

Author: dependabot[bot]

testing/plugins_integration/requirements.txt

@@ -2,7 +2,7 @@ anyio[curio,trio]==3.0.1
 django==3.2.2
 pytest-asyncio==0.15.1
 pytest-bdd==4.0.2
-pytest-cov==2.11.1
+pytest-cov==2.12.0
 pytest-django==4.2.0
 pytest-flakes==4.0.3
 pytest-html==3.1.1