1.6.0
FEA SLEP006: Metadata routing for `SelfTrainingClassifier` (#28494)
MNT Add author/license note where missing and add the linter (#29477)
API move BaseEstimator._validate_data to utils.validation.validate_data (#29696)
ENH remove _xfail_checks, pass directly to check runners, return structured output from check_estimator (#30149)