Update git submodules

Update git submodules

* Update kolla-ansible from branch 'master'
  to 2d7728ff321f9c9a6223f906d42288fd3668f9be
  - Merge "Make generation of prometheus.yml idempotent when using custom override files"
  - Make generation of prometheus.yml idempotent when using custom override files

    As the result from the find is not always sorted the same way, consecutive deployments would have a configuration file change, while it actually is not.

    Also, diffs are really hard to interpret, when some config parts have been moved up or down.

    Change-Id: I6f724de6ec46e0691639f0a64de5af9e248a27ff
    Resolves-bug: #2126635
    Signed-off-by: Michel Nederlof <michel.nederlof@nl.team.blue>