Update git submodules

Update git submodules

* Update docs/submodules/policy/engine.git from branch 'master'
  to 87b642029080fbbacfb06daba15104f988ab6be0
  - Merge "CHeckstyle and JUnit for base package in ONAP-REST"
  - CHeckstyle and JUnit for base package in ONAP-REST

    Added unit tests and fixed checkstyle and SONAR issues in the base
    package of ONAPE-REST

    There was a lot of knock-on automatic changes done by Eclipse when I
    renamed the class XACMLRestProperties to XacmlRestProperties so ignore
    the changes in all but the ONAP-REST package. I also didn't update the
    licenses on files on those classes because the changes were automatic.

    Issue-ID: POLICY-2131
    Change-Id: I28823c844b5192f8d56de76a727996b13e7ea4a6
    Signed-off-by: liamfallon <liam.fallon@est.tech>