fix(pre-commit): use single pytest dependency specifier (#91276)

[pytest>=8, <9] is parsed as two items; pip fails on '<9'.
Use ["pytest>=8,<9"] so pip gets one valid PEP 440 spec.
Pre-commit-only fix from closed #39109.

.pre-commit-config.yaml

@@ -64,7 +64,7 @@ repos:
         name: skills python tests
         entry: pytest -q -c skills/pyproject.toml skills
         language: python
-        additional_dependencies: [pytest>=8, <9]
+        additional_dependencies: ["pytest>=8,<9"]
         pass_filenames: false
         files: "^skills/.*\\.py$"