deps(dev): bump the major-dependencies group with 3 updates

Updates the requirements on [pytest-cov](https://github.com/pytest-dev/pytest-cov), [pytest-isort](https://github.com/stephrdev/pytest-isort) and [pytest](https://github.com/pytest-dev/pytest) to permit the latest version.

Updates `pytest-cov` to 5.0.0
- [Changelog](https://github.com/pytest-dev/pytest-cov/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest-cov@v3.0.0...v5.0.0)

Updates `pytest-isort` to 4.0.0
- [Changelog](https://github.com/stephrdev/pytest-isort/blob/master/CHANGELOG.rst)
- [Commits](stephrdev/pytest-isort@2.0.0...4.0.0)

Updates `pytest` to 8.1.1
- [Release notes](https://github.com/pytest-dev/pytest/releases)
- [Changelog](https://github.com/pytest-dev/pytest/blob/main/CHANGELOG.rst)
- [Commits](pytest-dev/pytest@6.0.0...8.1.1)

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

Signed-off-by: dependabot[bot] <support@github.com>

setup.py

@@ -44,12 +44,12 @@
         'tests': [
             'pylint-quotes~=0.2',
             'pylint>=2.11,<4.0',
-            'pytest-cov>=3,<5',
+            'pytest-cov>=3,<6',
             'pytest-instafail~=0.4',
-            'pytest-isort>=2,<4',
+            'pytest-isort>=2,<5',
             # 'pytest-pylint~=0.20',  #: Causing problems for some reason, even with 0.21
             'pytest-watch~=4.2',
-            'pytest>=6,<8',
+            'pytest>=6,<9',
             'yapf~=0.31',
         ]
     },