[DISCUSS] Removing deprecated state methods in 1.11

[Stephan Ewen]

Hi all!

There are a bunch of deprecated methods for state access:

  - RuntimeContext.getFoldingState(...)
  - OperatorStateStore.getSerializableListState(...)
  -  OperatorStateStore.getOperatorState(...)

All of them have been deprecated for around three years now. All have good
alternatives.

Time to remove them in 1.11?

Best,
Stephan