[VOL-5429] - update voltha-lib-go version to 7.6.6

Change-Id: Id6ebb05bba5c52a94161a08545e80106746e9cca
Signed-off-by: Sridhar Ravindra <sridhar.ravindra@radisys.com>
diff --git a/VERSION b/VERSION
index d738d02..16d34d4 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-3.6.6-dev1
+3.6.7-dev1