[EC2] For successful spot requests, fetch all created instances at once, and also tag them all at once.
[EC2] For successful spot requests, fetch all created instances at once,
and also tag them all at once.

This reduces the number of calls we make to EC2, without changing the
laniakea API functionality at all.

MozillaSecurity/laniakea,MozillaSecurity/laniakea,nth10sd/laniakea,nth10sd/laniakea