[Minor] Remove additional printing statement

Author: frankaging

pyvene/models/intervenable_base.py

@@ -117,7 +117,6 @@ def __init__(self, config, model, backend, **kwargs):
             config.representations
         ):
             _key = self._get_representation_key(representation)
-            print(f"Intervention key: {_key}")
 
             if representation.intervention is not None:
                 intervention = representation.intervention