apt upgrade action

[Adam Dyess]

Not sure if this is the most appropriate place for this bug, but I believe that all openstack charms would benefit with an action that can be used to apt-upgrade a unit to a specific version of the service at it's heart.

For example:
 saw that you've got ceph-mon, ceph-osd, ceph-radosgw that all have apt installed 'ceph'. Some may have different versions if those units were deployed at different times. In order to unify the version of ceph package installed across the cloud, one must ssh to each unit and apt install a specific version.

This would be nice if you could just:
  juju run-action ceph-mon/0 apt-upgrade
or
  juju run-action ceph-mon/0 apt-upgrade version='specific-version'

which would trigger:
sudo apt -y install ceph='12.2.12...'

[Chris MacNaughton (chris.macnaughton)]

It is generally recommended to use something like Landscape if the user needs to ensure that specific versions of things are on machines