fix: use correct TargetTags.positive_only field for sklearn 1.7 compatibility

sklearn 1.7 added __slots__ to tags dataclasses, making arbitrary attribute
assignment raise AttributeError. Replace required_positive (non-existent field)
with positive_only (correct field in sklearn 1.6 and 1.7).

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Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

Author: 3 people

python/abess/linear.py

@@ -1035,7 +1035,7 @@ def _more_tags(self):
     def __sklearn_tags__(self):
         tags = super().__sklearn_tags__()
         tags.regressor_tags.poor_score = True
-        tags.target_tags.required_positive = True
+        tags.target_tags.positive_only = True
         return tags
 
     def predict(self, X):