Update git submodules

* Update docs/submodules/sdc.git from branch 'master'
  to d7d87dc3a647e924bcf0e05e60c18f70cba3ed7b
  - Added unit tests for AbstractPropertyConstraint

    Improved the unit test coverage in the package
    org.openecomp.sdc.be.model.tosca.constraints

    Issue-ID: SDC-2327
    Signed-off-by: Piotr Borelowski <p.borelowski@partner.samsung.com>
    Signed-off-by: Krystian Kedron <k.kedron@partner.samsung.com>
    Change-Id: I094ab463cc010ecd48e062a1a806b3b907223228

diff --git a/docs/submodules/sdc.git b/docs/submodules/sdc.git
index 4f088f2..d7d87dc 160000 (submodule)
--- a/docs/submodules/sdc.git
+++ b/docs/submodules/sdc.git
@@ -1 +1 @@
-Subproject commit 4f088f2a33d9202238eab9fbc78b4eb7510d1438
+Subproject commit d7d87dc3a647e924bcf0e05e60c18f70cba3ed7b