Update git submodules

* Update docs/submodules/appc.git from branch 'master'
  to 231de316a76b195936545e35ccb59931ffde4128
  - fixed JUnits in 3 files
    
    Issue-ID: APPC-1859
    Change-Id: I8b27ea7dd6f0e30f05297544aaef795695e150f8
    Signed-off-by: Rupinder <rupinsi1@in.ibm.com>
    
1 file changed