Update git submodules

* Update docs/submodules/policy/engine.git from branch 'master'
  to 779125e31adbcc59a9864843b523bd6ed2751cbb
  - Unit/SONAR/Checkstyle in ONAP-REST
    
    Util package of ONAP-REST, with JUnit added and
    SONAR/Checkstyle issues addressed. In cases where a class name change
    caused an update in another package, the license header on files for
    those knock on changes are not updated.
    
    Issue-ID: POLICY-2131
    
    Change-Id: Ic134408efe76b9838f5607a07f1735d12bd41032
    Signed-off-by: liamfallon <liam.fallon@est.tech>
    
1 file changed