Fix dataset ok property not being cached because of different name.

The monkey-patching was placing the property under a name which differred from
that of the real function, with the latter being used to cache its returned
value.  Fixing the function name after cached property creation allows to use
the final, desired name to cache the value.

b2h5py/patch.py

@@ -23,6 +23,8 @@
 def B2Dataset_opt_dataset_ok(self):
     """Is this dataset suitable for Blosc2 optimized slicing"""
     return b2.opt_slicing_dataset_ok(self)
+# Fixing observable function name as it is used to cache the result.
+B2Dataset_opt_dataset_ok.func.__name__ = b2.opt_dataset_ok_prop
 
 
 def B2Dataset___getitem__(self, args, new_dtype=None):