Downgrade Common Cassandra version to 2.1.17 for Dublin

Change-Id: I0ae425343937389ff2f9bfd41701402398a63a82
Issue-ID: OOM-1832
Signed-off-by: mahendrr <mahendra.raghuwanshi@amdocs.com>
diff --git a/kubernetes/common/cassandra/values.yaml b/kubernetes/common/cassandra/values.yaml
index 51e82f3..d766b43 100644
--- a/kubernetes/common/cassandra/values.yaml
+++ b/kubernetes/common/cassandra/values.yaml
@@ -21,7 +21,7 @@
 
 # application image
 repository: nexus3.onap.org:10001
-image: library/cassandra:3.11
+image: library/cassandra:2.1.17
 pullPolicy: Always
 
 # flag to enable debugging - application support required