Scheme deprecated link is broken

[pcornelissen]

In https://github.com/material-foundation/material-color-utilities/blob/main/dart/lib/scheme/scheme.dart#L22C17-L22C106

you reference https://github.com/material-foundation/material-color-utilities/blob/main/make_schemes.md which is no longer available.

As a developer it would be nice how to migrate from the deprecated scheme to the proposed replacement, especially, when the new dynamic scheme is ARGB based and the color classes used in flutter don't return ARGB with the value getter (any longer?)