precooked script fails if the parent package has a scope

[Gaurav0]

I'm trying to fork Fastboot as @gaurav9576/ember-cli-fastboot. It uses ember-cli-addon-tests. The precook script fails because I'm using a scoped package name.

See https://github.com/Gaurav0/ember-cli-fastboot/actions/runs/6695374927/job/18190816737