Package.swift: fix deprecation warnings (package(name:url:from:), revision)

[BerkeleyDude]

When resolving or building with a recent Swift toolchain, Package.swift triggers deprecation warnings:

• package(name:url:from:) is deprecated: use package(url:from:) instead
• package(name:url:_:) with .revision / revision is deprecated: use specific requirement APIs

Please update the dependency declarations in Package.swift to the non-deprecated SPM APIs so the package builds without warnings.

Seen on Swift 6 / Xcode 16+ with GoogleSignIn-iOS 9.1.0.

[ImanMahmoudinasab]

This has been already reported via this issue: #576
let's thumbs up that issue to get more attention and quicker fix.