Why? I'd have thought CI is a place where per-second billing would be an advantage? A CI job is likely to take somewhere between 1 and 15 minutes, per second billing could be a significant saving for many users.
The price is actually $0.00005/second. :)
disclosure: I'm an engineer on the GCB team
I never really considered that. Perhaps it'd be profitable to actually use that capacity for something when it's idle...