Update git submodules

* Update docs/submodules/sdc.git from branch 'master'
  to d426d3a68f0cd5313cc7d543f74af97580e59493
  - Work around potential NullPointerExceptions in ToscaElementLifecycleOperation
    
    - Rewrite of `checkinToscaELement`
    - Extracted methods from `checkinToscaELement`
    
    Issue-ID: SDC-2964
    Signed-off-by: Chris Andre <chris.andre@yoppworks.com>
    Change-Id: I99d2c5aaa73b955ef5aa60eeb7644bb47ac12bd6
    
1 file changed