Update git submodules

* Update docs/submodules/appc.git from branch 'master'
  to 6e87544710647d9d1e55f3e8a72fe361d244e8b7
  - Suppression of long logs in GraphExecutor

    Logging full configuration files to info log was causing
    failures and timeouts on configuration operations in APPC.
    Some were removed already under this JIRA but this one was missed.

    Issue-ID: APPC-1489
    Change-Id: I619f2d1140095859092d6ceff6c7cb44855fb2e1
    Signed-off-by: Joss Armstrong <joss.armstrong@ericsson.com>

diff --git a/docs/submodules/appc.git b/docs/submodules/appc.git
index 9f4304d..6e87544 160000 (submodule)
--- a/docs/submodules/appc.git
+++ b/docs/submodules/appc.git
@@ -1 +1 @@
-Subproject commit 9f4304d6085d3cc9a2a242cdbd6a33c10cc91097
+Subproject commit 6e87544710647d9d1e55f3e8a72fe361d244e8b7