Review change: clarify comment
Review change: clarify comment

Include a link to the mongo docs for object ids to explain why sorting
by id yields predictable ordering in the tests.

mjs/juju,waigani/juju,anastasiamac/juju,dooferlad/juju,anastasiamac/juju,AdamIsrael/juju,axw/juju,gabriel-samfira/juju,howbazaar/juju,reedobrien/juju,mikemccracken/juju,waigani/juju,reedobrien/juju,dooferlad/juju,perrito666/juju,macgreagoir/juju,bac/juju,mikemccracken/juju,kat-co/juju,kat-co/juju,axw/juju,howbazaar/juju,perrito666/juju,ericsnowcurrently/juju,gabriel-samfira/juju,axw/juju,dooferlad/juju,waigani/juju,mikemccracken/juju,macgreagoir/juju,alesstimec/juju,bac/juju,bz2/juju,bac/juju,anastasiamac/juju,anastasiamac/juju,ericsnowcurrently/juju,alesstimec/juju,perrito666/juju,frankban/juju,perrito666/juju,howbazaar/juju,marcmolla/juju,dimitern/juju,gabriel-samfira/juju,howbazaar/juju,gabriel-samfira/juju,dimitern/juju,perrito666/juju,dooferlad/juju,ericsnowcurrently/juju,marcmolla/juju,bac/juju,axw/juju,anastasiamac/juju,marcmolla/juju,macgreagoir/juju,bac/juju,mjs/juju,dooferlad/juju,ericsnowcurrently/juju,ericsnowcurrently/juju,alesstimec/juju,frankban/juju,kat-co/juju,frankban/juju,axw/juju,kat-co/juju,mjs/juju,marcmolla/juju,macgreagoir/juju,bz2/juju,reedobrien/juju,AdamIsrael/juju,dimitern/juju,mjs/juju,mjs/juju,dimitern/juju,howbazaar/juju,alesstimec/juju,alesstimec/juju,gabriel-samfira/juju,AdamIsrael/juju,waigani/juju,mjs/juju,mikemccracken/juju,frankban/juju,reedobrien/juju,mjs/juju,marcmolla/juju,macgreagoir/juju,bz2/juju,AdamIsrael/juju,reedobrien/juju,mikemccracken/juju,bz2/juju,frankban/juju,dimitern/juju,bz2/juju,kat-co/juju