Retire the policyengine-core#559 input-record workaround now that core 3.32.27 fixes it #2260

policyengine-core 3.32.27 contains PolicyEngine/policyengine-core#561 ("Keep the record of set_input values in step with storage"), which fixes PolicyEngine/policyengine-core#559: Holder.delete_arrays now forgets the record of an input it deletes, and Simulation.clone gives each clone its own copy of _user_input_keys and an empty _user_input_contexts.

PE-UK still carries its own workaround for #559 in policyengine_uk/simulation.py and policyengine_uk/utils/supplied_inputs.py:

• a Simulation.clone override that copies _user_input_keys and _user_input_contexts;
• a Simulation.delete_arrays override and a Simulation.calculate hook that call drop_missing_supplied_inputs;
• SUPPLIED_INPUT_VARIABLES, which limits the supplied-input helpers to the variables the calculate hook keeps in step.

Once the floor is policyengine-core>=3.32.27, these duplicate what core does and can go. The helpers (supplied_input, supplied_input_periods) keep reading core's record.