[Preview] Embedded Swift support in Swift Testing

Hi Swift friends (and… Swift enemies?)! I'm here with an exciting new update about Swift Testing. For those of you who keep a close eye on Swift Testing's GitHub repository, you may have noticed a lot of changes landing recently with the label embedded-swift on them. Well, those changes weren't just for fun, you know: Swift Testing now has fully-functional experimental support for Embedded Swift. 🥳 Swift 6.4 introduced several major changes to Embedded Swift that have let us make...