Switch from installing cmake and ninja in cibuildwheel before step to…

… build-system requires

pyproject.toml

@@ -1,15 +1,9 @@
 [build-system]
-requires = ["setuptools>=64", "wheel", "scikit-build", "setuptools_scm>=8"]
+requires = ["setuptools>=64", "wheel", "scikit-build", "setuptools_scm>=8", "cmake>=3.21.4", "ninja>=1.10.2.2; platform_system!='Windows'"]
 build-backend = "setuptools.build_meta"
 
 [tool.cibuildwheel]
 build = "cp39-*"
-before-all = [
-    "pipx install -f cmake==3.21.4",
-    "cmake --version",
-    "pipx install -f ninja==1.10.2.2",
-    "ninja --version",
-]
 test-command = [
   "swig -version",
   "swig -pcreversion",