Swift 6.0 todo

[meatball133]

Swift 6.0

This will likely be one of the largest updates to the track to this date.
To make the track more future proof and inline with the direction the language is going, will we switch from XCTest to Swift-Testing.
This is a huge undertaking which involves rewriting 100+ test files, this will also require a brand new test runner.

Tooling

• New Test runner ([2.0]: Swift 6 support swift-test-runner#58)
• Updated Test Generator (Update generator to swift 6.0 #782)

Exercises

• Armstrong Numbers, update to include int128 tests (postponed due to missing pow function) ([Swift 6.0]: Update armstrong number with new testing files #784)
• [Swift 6]: Update Exercises batch 1 #785

Update all test file to Swift testing