[3.15] Revert "[3.15] gh-146452: Improve locking granularity in pickle's batch_dict_exact and fix race condition (GH-150025) (#150039)"

[3.15] Revert "[3.15] gh-146452: Improve locking granularity in pickle's batch_dict_exact and fix race condition (GH-150025) (#150039)" #260333