chore(deps-py): update pydantic requirement in /hugr-py

Updates the requirements on [pydantic](https://github.com/pydantic/pydantic) to permit the latest version.
- [Release notes](https://github.com/pydantic/pydantic/releases)
- [Changelog](https://github.com/pydantic/pydantic/blob/main/HISTORY.md)
- [Commits](pydantic/pydantic@v2.8.0...v2.9.1)

---
updated-dependencies:
- dependency-name: pydantic
  dependency-type: direct:production
...

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

hugr-py/pyproject.toml

@@ -26,7 +26,7 @@ classifiers = [
 ]
 
 dependencies = [
-    "pydantic>=2.8,<2.9",
+    "pydantic>=2.8,<2.10",
     "pydantic-extra-types>=2.9.0",
     "semver>=3.0.2",
     "graphviz>=0.20.3",