ScopedState can not be re-entered (regression caused by Batched DoFn worker changes)

We've observed some regressions in internal pipelines. We've narrowed the root cause down to https://github.com/apache/beam/pull/17384 - the worker changes for Batched DoFns.

I still don't understand the root cause, but given this change can lead to a regression in pipelines that don't use the feature I think we should roll it back.