Fix get_vector_length incorrectly returning for shared variable without static shape

Author: Abhinav-Khot

pytensor/tensor/sharedvar.py

@@ -3,7 +3,6 @@
 import numpy as np
 
 from pytensor.compile import SharedVariable, shared_constructor
-from pytensor.tensor import _get_vector_length
 from pytensor.tensor.type import TensorType
 from pytensor.tensor.variable import TensorVariable
 
@@ -51,11 +50,6 @@ def zero(self, borrow: bool = False):
             self.container.value = 0 * self.container.value
 
 
-@_get_vector_length.register(TensorSharedVariable)
-def _get_vector_length_TensorSharedVariable(var_inst, var):
-    return len(var.get_value(borrow=True))
-
-
 @shared_constructor.register(np.ndarray)
 def tensor_constructor(
     value,