Update git submodules

* Update docs/submodules/appc.git from branch 'master'
  to 19bb17c4b16ee955cdec6db9ddc2af25845df062
  - Test coverage in XInterfaceService
    
    Increased coverage from 68% to 100%
    
    Issue-ID: APPC-1436
    Change-Id: If9f1670ba9955325bf938d7edf3d7d67bb48088c
    Signed-off-by: Joss Armstrong <joss.armstrong@ericsson.com>
    
1 file changed