Update git submodules

* Update docs/submodules/usecase-ui.git from branch 'master'
  to 537a77b78b576c08e3f3aabdd468d91ff76ec915
  - feat: add csmf slice business management of 5G Slicing Management
    
    Change-Id: Ie491a10e2e9540b6e3703ad51cc1bd0e7e164610
    Issue-ID: USECASEUI-369
    Signed-off-by: cyuamber <xuranyjy@chinamobile.com>
    
1 file changed