When building for the iOS platform, if you encounter this issue:
[!] `GoogleAppMeasurement` requires CocoaPods version `>= 1.10.2`, which is not satisfied by your current version, `1.10.0`.
This is referring to the cocoaPods version Play Services Resolver is using. Go to Assets > PlayServicesResolver > iOS Resolver > Install Cocoapods, a popup will appear explaining from which cocoapods location Play Services Resolver is using. Make sure you successfully update the version of that cocoapod executable, and this issue should be resolved.
For more information, see documentation on Unity Mediation.