Type of key in keyword argument is always str

See
https://peps.python.org/pep-0484/#arbitrary-argument-lists-and-default-argument-values.
But since the value is Any, the type hint may really not be particularly
useful here.

Author: hattne

build.py

@@ -123,7 +123,7 @@ def generate_combined_checksum(root):
     return hash_files(*gen_files, extra_data=extra_data)
 
 
-def build(setup_kwargs: Dict[str, Any]) -> None:
+def build(**setup_kwargs: Any) -> None:
     # Validate that the SWIG wrappers are generated from the latest
     # sources (if we have them)
     swigdir = PYCBF_ROOT / "SWIG"