Add `macos` CI stage
Created by: cmichi
Adds a macos
CI stage analogue to the Windows CI stage which we already have.
This is a follow-up to https://github.com/paritytech/ink/pull/1066.
Created by: cmichi
Adds a macos
CI stage analogue to the Windows CI stage which we already have.
This is a follow-up to https://github.com/paritytech/ink/pull/1066.