Update git submodules

* Update docs/submodules/usecase-ui.git from branch 'master'
  to e88155c2a4046974387fcb64406a28ed672a63d4
  - Dashboard interface front-end development
    
    Change-Id: Ife8dbb89e9a5d465e1c3b6b6a290059f376b673b
    Issue-ID: USECASEUI-214
    Signed-off-by: guochuyicmri <guochuyi@chinamobile.com>
    
1 file changed