[Feature] Disable Specific Item from array on UiSchema

Prerequisites

• I have read the documentation; https://react-jsonschema-form.readthedocs.io/en/latest/usage/arrays/

Description

According to the doc it is a new Feature : I can disable specific item (no disable additionnal properties) with index number (no conditionnal because is for javascript dynamic logic).

Steps to Reproduce

there is no step to reproduce because is a UISchema Feature

Expected behavior

have option on uischema let me fill a index wich the whole item is disable (object or string/number)

Actual behavior

No possibilities to fill an index which disable specific item from array

Version

v3.0.1 if something have this feature then the doc need update please