Building for iOS 16+

[WaleedAmer]

I'm unable to build my package to iOS

When running swift build --configuration debug --destination destination.json I get the following error/note:

• "error: 'trimmingPrefix' is only available in iOS 16.0 or newer"
• note: add 'if #available' version check

Seems like the swift-syntax package targets iOS v13, not sure if that's the issue but changing it to v16 did not fix the issue for me

[migueldeicaza]

The trimming prefix operation is a build-time limitation, not a runtime limitation, so I am not sure why this is showing up on iOS.