Update git submodules

* Update docs/submodules/usecase-ui.git from branch 'master'
  to 781aad0ded84716dce4cd88f661e33d0cea852e8
  - feat: optimize the code for the customer page
    
    Change-Id: I8dc434c8ab90fdf3b78b05b15e5f210980922724
    Issue-ID: USECASEUI-307
    Signed-off-by: cyuamber <xuranyjy@chinamobile.com>
    
1 file changed