This has been moved to framework in https://github.com/ppy/osu-framework/pull/4285.
"Change the `ReadAsync` method call to use the `Stream.ReadAsync(Memory<byte>, CancellationToken)` overload"
# Conflicts: # osu.Game/IO/OsuStorage.cs
Forgot to change this while changing the param from string to Storage
Now asserting instead of an if-statement, change cast from OsuStorage to MigratableStorage and make internal virtual properties protected.
This reverts commit ef8375b442.
ef8375b442