Update git submodules

* Update docs/submodules/usecase-ui.git from branch 'master'
  to 237ed72e04ae121297a0594be069a26db49d0f5b
  - New committer promotion for Ran Xu
    
    Change-Id: Ia18c4fb1853c2d9367dfb89e4b7aa8a00e42e791
    Issue-ID: USECASEUI-347
    Signed-off-by: shentao999 <shentao@chinamobile.com>
    
1 file changed