Update git submodules

* Update docs/submodules/integration.git from branch 'master'
  to 73c2d81546decf3b9356fa186f5054592975c75d
  - Update E2E_network_slicing doc
    
    Issue-ID: INT-1468
    Signed-off-by: krishnaa96 <krishna.moorthy6@wipro.com>
    Change-Id: Ib11a36000ae6c926c990786172d250f586409f3d
    
1 file changed