Update git submodules

* Update charm-watcher from branch 'master'
  to 27c563dd5e90af4371a5124f7358b186a8a45d02
  - Add zaza-openstack-tests testing.
    
    This change expands the testing bundles to deploy a fully functional
    cloud and run the testing class WatcherTests which uses the
    vm_workload_consolidation strategy[0].
    
    [0] https://docs.openstack.org/watcher/latest/strategies/basic-server-consolidation.html
    
    Func-Test-Pr: openstack-charmers/zaza-openstack-tests#1101
    Change-Id: I5a1d9ef50ce16d553a06382e0825fcbb2d12e887