Amendment https://github.com/apple/swift-evolution/pull/1392 is incomplete.
Compilation fails, when class with both async and async method versions trying to satisfy protocol requirement with both sync and async methods or just async method implementation.
Throws several issues:
- error: type 'TestClass' does not conform to protocol 'TestProtocol'
- note: multiple matching functions named 'read()' with type '() async -> ()'