Update git submodules

* Update docs/submodules/dovetail from branch 'stable/fraser'
  - Reviewer guide update for OVP 2018.08 release

    JIRA: DOVETAIL-701

    Change-Id: I940bdd16762dd36ee338f41e5b2aab352c70600f
    Signed-off-by: dimitris.tsiolakis <dmts@intracom-telecom.com>
    (cherry picked from commit 0727b542015f7f3718eda435396d34aec5ac1c80)

diff --git a/docs/submodules/dovetail b/docs/submodules/dovetail
index 5cf7a06..8e7906b 160000 (submodule)
--- a/docs/submodules/dovetail
+++ b/docs/submodules/dovetail
@@ -1 +1 @@
-Subproject commit 5cf7a06c5bed1139821ac5e0a95e5db5caa761f3
+Subproject commit 8e7906bb67bbd3ba524510633b3613e67cb97689