Revert "ensure dtypes match"

This reverts commit 54f4b53.

Author: jaffourt

sklearn/utils/validation.py

@@ -2612,18 +2612,15 @@ def _check_pos_label_consistency(pos_label, y_true):
         # Compute classes only if pos_label is not specified:
         xp, _, device = get_namespace_and_device(y_true)
         classes = xp.unique_values(y_true)
-        cls_dtype = classes.dtype
         if (
             (_is_numpy_namespace(xp) and classes.dtype.kind in "OUS")
             or classes.shape[0] > 2
             or not (
-                xp.all(classes == xp.asarray([0, 1], dtype=cls_dtype, device=device))
-                or xp.all(
-                    classes == xp.asarray([-1, 1], dtype=cls_dtype, device=device)
-                )
-                or xp.all(classes == xp.asarray([0], dtype=cls_dtype, device=device))
-                or xp.all(classes == xp.asarray([-1], dtype=cls_dtype, device=device))
-                or xp.all(classes == xp.asarray([1], dtype=cls_dtype, device=device))
+                xp.all(classes == xp.asarray([0, 1], device=device))
+                or xp.all(classes == xp.asarray([-1, 1], device=device))
+                or xp.all(classes == xp.asarray([0], device=device))
+                or xp.all(classes == xp.asarray([-1], device=device))
+                or xp.all(classes == xp.asarray([1], device=device))
             )
         ):
             classes = _convert_to_numpy(classes, xp=xp)