Regression when using `sort(using: Comparator)`

[tgrapperon]

Description

Since the release 1.0.1, sorting an identified array using a KeyPathComparator fails when it internally accesses the subscript. It was previously working on v1.0.0

Checklist

• [X] If possible, I've reproduced the issue using the main branch of this package.
• [X] This issue hasn't been addressed in an existing GitHub issue or discussion.

Expected behavior

func testIdentifiedArraySort() {
  struct Item: Identifiable {
    let id: Int
  }
  var items: IdentifiedArrayOf<Item> = [Item(id: 3), Item(id: 2), Item(id: 1)]
  items.sort(using: KeyPathComparator(\.id))
  XCTAssertEqual([1, 2, 3], items.map(\.id))
}

Actual behavior

It crashes when it hits the precondition in the subscript (we removed an element, but its id can already be found elsewhere in the array we're working on).

Steps to reproduce

The following test should pass (and passes on v1.0.0):

func testIdentifiedArraySort() {
  struct Item: Identifiable {
    let id: Int
  }
  var items: IdentifiedArrayOf<Item> = [Item(id: 3), Item(id: 2), Item(id: 1)]
  items.sort(using: KeyPathComparator(\.id))
  XCTAssertEqual([1, 2, 3], items.map(\.id))
}

Note that sorting using the closure comparison works.

Identified Collections version information

1.0.1

Destination operating system

iOS 17

Xcode version information

Version 15.3 (15E5202a)

Swift Compiler version information

swift-driver version: 1.90.11.1 Apple Swift version 5.10 (swiftlang-5.10.0.13 clang-1500.3.9.4)
Target: arm64-apple-macosx14.0