Previously, creating an automation object was the last instruction. It
is easier to describe what to expect at each step when the last step
is to add an update marker in the file to be updated, since the next
thing that should happen is that the automation makes an update as a
consequence.
This commit shifts the sections around so that setting up the
GitRepository and ImageUpdateAutomation are done earlier, and
migrating each file are done after that, and completes the steps
described including checking the expected status at each stage.
Signed-off-by: Michael Bridgen <michael@weave.works>