Fix minimum platforms in `Package.swift` to match deps#1

pcfba merged 1 commit intogoogleads:maingoogleads/google-ads-on-device-conversion-ios-sdk:mainfrom

andrewheard:ah/spm-min-platformsandrewheard/google-ads-on-device-conversion-ios-sdk:ah/spm-min-platformsCopy head branch name to clipboard