[5.x] Ensure minimum-stability is dev before requiring new addon

[duncanmcclean]

This pull request fixes an issue with the php please make:addon command where Composer will throw an error when requiring a new addon when an app's minimum-stability setting is anything other than dev.

[jasonvarga]

Ideally we should avoid that.

If you don't have mininum-stability, you're still able to do composer require my/addon dev-master and it'll work.

It's just a matter of figuring out what branch it needs. dev-master or dev-main. Composer figures it out under the hood somehow. Maybe we can lift the logic from there. 🤔