Update git submodules

Update git submodules

* Update docs/submodules/oom.git from branch 'master'
  to 52b046a351ce1551a338c1f9862366f45cf4929f
  - Merge "[APPC] Use common secret tamplate for mariadb-galera credentials"
  - [APPC] Use common secret tamplate for mariadb-galera credentials

    Use init container construction & common secret template to remove
    hardcoded mysql db credentials.

    For now credentials are still hardcoded in the values file to avoid
    making too many changes at once.

    I also had to make properties files writeable because appc uses some
    weird design and modifies them inside main container while starting
    odl.

    Issue-ID: OOM-2275
    Signed-off-by: Krzysztof Opasiak <k.opasiak@samsung.com>
    Change-Id: Ie36522fc1fdf92a382d5f25a54d4cb150b57ea35