Remove non-existent kwargs in ast.Call() call

See https://docs.python.org/3.10/library/ast.html#abstract-grammar for a reference on the attributes `ast.Call` takes.

A future version of mypy will give a type error for this code (python/typeshed#11880).

lib/streamlit/runtime/scriptrunner/magic.py

@@ -171,8 +171,6 @@ def _build_st_write_call(nodes):
         ),
         args=nodes,
         keywords=[],
-        kwargs=None,
-        starargs=None,
     )