Move conftest so it doesn't get packaged in release

Author: ntjohnson1

python/datafusion/conftest.py conftest.pypython/datafusion/conftest.py renamed to conftest.py

@@ -17,11 +17,10 @@
 
 """Pytest configuration for doctest namespace injection."""
 
+import datafusion as dfn
 import numpy as np
 import pytest
 
-import datafusion as dfn
-
 
 @pytest.fixture(autouse=True)
 def _doctest_namespace(doctest_namespace: dict) -> None: