build(deps): bump pytest-cov in the test-dependencies group

Bumps the test-dependencies group with 1 update: [pytest-cov](https://github.com/pytest-dev/pytest-cov).


Updates `pytest-cov` from 6.0.0 to 6.1.1
- [Changelog](https://github.com/pytest-dev/pytest-cov/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest-cov@v6.0.0...v6.1.1)

---
updated-dependencies:
- dependency-name: pytest-cov
  dependency-version: 6.1.1
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: test-dependencies
...

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

Author: dependabot[bot]

pyproject.toml

@@ -37,7 +37,7 @@ pyvistaqt = [
 tests = [
     "pytest==8.3.5",
     "pytest-pyvista==0.1.9",
-    "pytest-cov==6.0.0",
+    "pytest-cov==6.1.1",
     "pyside6==6.9.0",
 ]