Updating version of charts for VOLTHA 2.8

Change-Id: Ib308594ef03fac7c271fa1bb084fbd0d6d60f82e
diff --git a/VERSION b/VERSION
index 834f262..dbe5900 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-2.8.0
+2.8.1