Update git submodules

Update git submodules

* Update docs/submodules/so.git from branch 'master'
  to 6acf5b81168724ca4c889daf9b9cfcc5100e02e1
  - Merge "SO CDS Metadata ingestion"
  - SO CDS Metadata ingestion

    Add support for controller_actor ingestion
    Add support for blueprint in service
    Add support for skip conf flag in vf module
    Ingest new properties into SO database
    Sample csar files are cleaned without comment and description

    Issue-ID: SO-2313
    Change-Id: I657f997faf33a366f3c234c3e41b164275beedac
    Signed-off-by: eeginux<henry.xie@est.tech>