Seems the deploy SSH key wasn't added to private repositories we manage:
----------
          ID: staging_private_repository
    Function: git.latest
        Name: ssh://vcs@devcentral.nasqueron.org:5022/source/private-staging.git
      Result: False
     Comment: Failed to update submodules: Unable to authenticate using identity file:
              Submodule 'wwwroot/dereckson.be/watai' (git@bitbucket.org:dereckson/watai.dereckson.be.git) registered for path 'wwwroot/dereckson.be/watai'