build: add clang-format to build-system requires

The codegen pipes generated headers/sources through `clang-format`
to satisfy CI's style check.  CI containers (metax, moore, cambricon)
do not ship a system `clang-format` binary, so cmake-time codegen
fails with `FileNotFoundError: clang-format`.

Pin it as a build dep so `pip install` provisions `clang-format`
into the build env before scikit-build invokes cmake.

Author: voltjia

pyproject.toml

@@ -1,5 +1,5 @@
 [build-system]
-requires = ["scikit-build-core", "pybind11", "libclang", "pyyaml"]
+requires = ["scikit-build-core", "pybind11", "libclang", "pyyaml", "clang-format"]
 build-backend = "scikit_build_core.build"
 
 [project]