Upgrade-series command hint should be indented

[Tim McNamara]

Consider a model that's been set up as follows:

  $ juju add-model testing
  $ juju deploy rabbitmq-server -n 3 --series xenial

Preparing an upgrade presents output that ends with "juju upgrade-series 0 complete". This reads as a completion indicator, not a recommendation. We should indent the line to make this clear.

  $ juju upgrade-series 0 prepare bionic
  WARNING: This command will mark machine "0" as being upgraded to series "bionic".
  This operation cannot be reverted or canceled once started.
  Units running on the machine will also be upgraded. These units include:
    rabbitmq-server/0

  Leadership for the following applications will be pinned and not
  subject to change until the "complete" command is run:
    rabbitmq-server

  Continue [y/N]?y
  machine-0 started upgrade series from "xenial" to "bionic"
  rabbitmq-server/0 pre-series-upgrade hook running
  rabbitmq-server/0 pre-series-upgrade completed
  machine-0 binaries and service files written

  Juju is now ready for the series to be updated.
  Perform any manual steps required along with "do-release-upgrade".
  When ready, run the following to complete the upgrade series process:

  juju upgrade-series 0 complete

[Canonical Juju QA Bot (juju-qa-bot)]

This bug has not been updated in 2 years, so we're marking it Low importance. If you believe this is incorrect, please update the importance.