build: remove cmake as a build-system dependency

Instead, add the tool.scikit-build.cmake.version attribute, and
link it to CMakeLists so it automatically checks if the required
cmake version is already installed. This prevents the unnecessary
installation of cmake python wheels.

Author: stickies-v

pyproject.toml

@@ -1,6 +1,5 @@
 [build-system]
 requires = [
-    "cmake>=3.15",
     "scikit-build-core"
 ]
 build-backend = "scikit_build_core.build"
@@ -23,6 +22,7 @@ test-command = "pytest {project}/test"
 test-extras = ["test"]
 
 [tool.scikit-build]
+cmake.version = "CMakeLists.txt"
 wheel.packages = ["src/pbk"]
 wheel.install-dir = "pbk"
 sdist.include = [