Find recommendation to write gitlab-ci.yml script with yarn instead of npm

In our project, most of node_modules are runned by yarn instead of npm so we produce yarn.lock rather than package-lock.json. Further, it seems npm ci is not able to replace by same command yarn ci.

If you have any recommendation to replace npm things to yarn on .gitlab-ci.yml, it would be extremely helpful that makes our code consistent.

I mean we would like to follow up the guideline that we write yarn into gitlab ci for running cypress test into Schedules.

Thanks.