PYSEC-2026-4224 Hydra: Optuna custom_search_space can resolve and execute untrusted callables via get_method

Summary hydra-optuna-sweeper accepted a configuration-controlled dotted path in hydra.sweeper.customsearchspace, resolved it with the lower-level hydra.utils.getmethod API, and later invoked the returned callable. Hydra's object-lookup helpers intentionally trust their input and do not apply the...