revert change to _addsub_object_array

Author: simonjayhawkins

pandas/core/arrays/datetimelike.py

@@ -1334,8 +1334,9 @@ def _addsub_object_array(self, other: np.ndarray, op):
         result : same class as self
         """
         assert op in [operator.add, operator.sub]
-        if len(other) == 1 and self.ndim == 1:
+        if len(other) == 1:
             # If both 1D then broadcasting is unambiguous
+            # TODO(EA2D): require self.ndim == other.ndim here
             return op(self, other[0])
 
         warnings.warn(