chore(*): rename deprecated X-ConditionMachineBootID

This was changed to X-ConditionMachineID.
See https://github.com/coreos/fleet/blob/d647e00d38ad55c475b4b1c32d29ed696dc9e2c6/job/job.go#L23-L24
Merge pull request #1716 from carmstrong/remove_deprecated_fleet

chore(*): rename deprecated X-ConditionMachineBootID