Add machineRemovalsC to the migration ignored list
Add machineRemovalsC to the migration ignored list

The prechecks will guarantee that there are no dead machines remaining
when a migration starts, so there'll never be any machine removals that
need to be migrated. (Confirmed by Menno.)

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