BUG: add workaround for pytest assertion rewriting overreach

closes scipygh-22236
see discussion of upstream bug from pytest-dev/pytest#10845 (comment)

Author: lucascolley

scipy/ndimage/_ndimage_api.py

@@ -12,4 +12,4 @@
 from ._measurements import *   # noqa: F403
 from ._morphology import *   # noqa: F403
 
-__all__ = [s for s in dir() if not s.startswith('_')]
+__all__ = [s for s in dir() if not s.startswith(('_', '@'))]