This part of the guide assumes that native ink has been migrated as per instructions in contracts.md.
Update openbrush dependency to openbrush = { git = "https://github.com/727-Ventures/openbrush-contracts", tag = "3.0.0-beta" }.
Note the organization change (from Supercolony-net to 727-Ventures) and the tag.
As per contracts.md, the compatible ink dependency is rev = "4655a8b4413cb50cbc38d1b7c173ad426ab06cde".