Build(deps-dev): update pytest-xdist requirement from >=3.6.1 to >=3.8.0

Updates the requirements on [pytest-xdist](https://github.com/pytest-dev/pytest-xdist) to permit the latest version.
- [Release notes](https://github.com/pytest-dev/pytest-xdist/releases)
- [Changelog](https://github.com/pytest-dev/pytest-xdist/blob/master/CHANGELOG.rst)
- [Commits](pytest-dev/pytest-xdist@v3.6.1...v3.8.0)

---
updated-dependencies:
- dependency-name: pytest-xdist
  dependency-version: 3.8.0
  dependency-type: direct:development
...

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

Author: dependabot[bot]

pyproject.toml

@@ -48,7 +48,7 @@ dev = [
     "pytest>=8.3.5",
     "pytest-benchmark>=5.1.0",
     "pytest-cov>=6.0.0",
-    "pytest-xdist[psutil]>=3.6.1",
+    "pytest-xdist[psutil]>=3.8.0",
     "ruff>=0.11.0",
     "sphinx>=8.2.3",
     "tox>=4.25.0",