Update macOS minimum version documentation to 10.13

[jmagman]

Page URL

https://docs.flutter.dev/deployment/macos#review-xcode-project-settings

Page source

No response

Describe the problem

References to Flutter supports macOS 10.11 and later. should become Flutter supports macOS 10.13 and later., etc.

This should wait until https://github.com/flutter/flutter/pull/107689 gets to a stable release.

See also pending iOS version of this request https://github.com/flutter/website/issues/7037.

Expected fix

No response

Additional context

No response