chore(deps): Update pytest-cov requirement from <6,>=4 to >=4,<7

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@v4.0.0...v6.0.0)

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

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

pyproject.toml

@@ -60,7 +60,7 @@ dev = [
     "pylsp-rope >=0.1,<0.2",
     "pytest >=7.1,<9.0",
     "pytest-asyncio >=0.20,<0.25",
-    "pytest-cov >=4,<6",
+    "pytest-cov >=4,<7",
     "python-lsp-server >=1.5,<2.0",
     "reuse >=4.0,<5.0",
     "ruff >=0.8.0",