VOL-2232 restrict kafka readiness to connectivity-related errors

Change-Id: I31d3d2a8ded41bb762a9105781458a50f05ec8c3
diff --git a/VERSION b/VERSION
index c36c648..be067c7 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-2.2.17
+2.2.18-dev