The root cause is the removal of Docker from the GitHub action, that happened in v4.0.0. We made that change to fix a variety of issues, reported to us by multiple of our customers, all coming from the use of Docker.
You can read more about this change in this community post.
Removing Docker fixed many of the issues our users had, but unfortunately seems to have came with the cost of not being able to support alpine from the day 1. We may look into this in the future, but there are currently no plans to specifically overcome alpine limitations on unzip.
So I would first try to see if we can easily fix your pipeline by removing the container, to make sure that your issue actually comes from alpine.
Best regards,
Antonio