Mac build agent in the cloud

Has anyone tried using a cloud hosted mac agent to build Monogame apps for iOS? If so, would you care to post a tutorial? =)

I gave it a go but keep getting an error:

Starting: Build Xamarin.iOS solution …
Task : Xamarin.iOS
Description : Build an iOS app with Xamarin on macOS

Errors:
/iOS.csproj could not import “$(MSBuildExtensionsPath)\MonoGame\v3.0\MonoGame.Content.Builder.targets”