Use the `NSOperatingSystemVersion` struct provided by the cocoa crate
instead of our own. Additionally we can directly use
`isOperatingSystemAtLeastVersion` instead of manually implementing
version comparison logic.

The `isOperatingSystemAtLeastVersion` instance method has been available
since MacOS 10.10, which released a decade ago.

Documentation for `isOperatingSystemAtLeastVersion `:
https://developer.apple.com/documentation/foundation/nsprocessinfo/1414876-isoperatingsystematleastversion

Release Notes:

- N/A