Remove unnecessary type hints

Author: michaelosthege

pytensor/tensor/subtensor.py

@@ -222,7 +222,7 @@ def as_index_literal(
         return None
 
     if isinstance(idx, ScalarConstant):
-        return cast(int | None, idx.data)
+        return cast(int, idx.data)
 
     if isinstance(idx, TensorConstant):
         return cast(int, idx.data.item())
@@ -253,7 +253,7 @@ def get_canonical_form_slice(
 def get_canonical_form_slice(
     theslice: ScalarVariable | TensorVariable,
     length: int | np.integer | ScalarVariable | TensorVariable,
-) -> tuple[slice | ScalarVariable, int]: ...
+) -> tuple[ScalarVariable, int]: ...
 
 
 def get_canonical_form_slice(