SetRequiredDeep doesn't remove optional modifiers from tuples

[som-sm]

Bug description

Refer to the note in this comment.

import {SetRequiredDeep} from "type-fest";

type Test = SetRequiredDeep<{a: [string?]}, "a.0">; // doesn't remove the `?` modifier
//  actual: {a: [string?]} // returns the same thing
//  expected: {a: [string]}

Repro

https://tsplay.dev/NajlBm