deps(dev): update pytest-cov requirement from <6.0,>=4.1 to >=4.1,<7.0

Updates the requirements on [pytest-cov](https://github.com/pytest-dev/pytest-cov) to permit the latest version.
- [Changelog](https://github.com/pytest-dev/pytest-cov/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest-cov@v4.1.0...v6.0.0)

---
updated-dependencies:
- dependency-name: pytest-cov
  dependency-type: direct:development
...

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

setup.py

@@ -44,7 +44,7 @@
         'tests': [
             'pylint-quotes~=0.2',
             'pylint>=2.17,<4.0',
-            'pytest-cov>=4.1,<6.0',
+            'pytest-cov>=4.1,<7.0',
             'pytest-instafail~=0.5',
             'pytest-isort>=3.1,<5.0',
             'pytest-mock~=3.11',