How to use aliasify on a data package?

[azlam-abdulsalam]

Discussed in https://github.com/Accenture/sfpowerscripts/discussions/751

^{Originally posted by ppeersgi November 4, 2021}
We have created an environment specific data package with the same folder structure as below (including a default directory):

But getting an error after quickbuild and deploy on a scratch org:

Error: Aliasfied package 'managed-data-pre-env-specific' does not have an alias with 'BETA-2101'' or 'default' directory