fix: skip build in CI

[achingbrain]

In CI we always build after an install, which happens before testing so we can skip the build step since all build output should have been cached.

[SgtPooki]

Just thinking out loud: IIRC there was a rebuild flag I added a while back to handle a case similar to this. Not sure exactly how this is different (on phone and not able to dive in as deeply right now)