pre-commit is not needed to run tests.

--- traitlets-5.15.0/pyproject.toml.orig
+++ traitlets-5.15.0/pyproject.toml
@@ -36,7 +36,6 @@
     "mypy>=1.7.0",
     # see https://github.com/python/mypy/issues/20454
     "mypy>=1.7.0,<1.19 ; platform_python_implementation == 'PyPy'",
-    "pre-commit",
     "pytest-mock",
     "pytest>=7.0,<8.2",
 ]