Update git submodules

* Update docs/submodules/appc.git from branch 'master'
  to 519ff3f34b42e41fbd995fe0c08a75f60a00be14
  - RequestContext.java - sonar fixes
    
    RequestContext.java - sonar fixes
    
    Issue-ID: APPC-1564
    Change-Id: I334c1f07403cf246efb3413639fdb26cc08556af
    Signed-off-by: Driptaroop Das <driptaroop.das@in.ibm.com>
    
1 file changed