Increase IPHONEOS_DEPLOYMENT_TARGET to 9.0, for Xcode 16 Compatibility

[gemmakbarlow]

In Xcode 16.2 Beta 2, iOS Carthage builds will fail unless the minimum OS version is bumped. Given tvOS minimum is set to 9.0, this seemed appropriate.

The error I originally ran into, prompting this change, is shown below -

clang: error: SDK does not contain 'libarclite' at the path '/Applications/Xcode-16.0.0-Beta.2.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/arc/libarclite_macosx.a'; try increasing the minimum deployment target

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