chore(deps-dev): bump pytest-cov from 4.1.0 to 7.0.0 in /backend

Bumps [pytest-cov](https://github.com/pytest-dev/pytest-cov) from 4.1.0 to 7.0.0.
- [Changelog](https://github.com/pytest-dev/pytest-cov/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest-cov@v4.1.0...v7.0.0)

---
updated-dependencies:
- dependency-name: pytest-cov
  dependency-version: 7.0.0
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]