There's no "billboard.js defined in the packages listed ab ove
You didn't provide a reproduction. We can'T help you without a reproduction, that's why one is mandatory.
This problem is likely not related to vue-cli since package resolution is webpack/npm's job, not vue-cli's. I may be wrong but can't judge differently since you didn't provide any information to work with.
Version
3.9.3
Environment info
Steps to reproduce
Nil
What is expected?
The app.js should have the lastest version of Billboard.js as mentioned in the package.json
What is actually happening?
The node_modules folder contains the latest specified version of Billboard.js, but after packaging, the app.js contains an older version.