Cluster: fix clusterBlacklistAddNode() by setting right expire time.

The hash table value should be set to now + 60 seconds otherwise it
expires immediately.

src/cluster.c

@@ -714,7 +714,7 @@ void clusterBlacklistAddNode(clusterNode *node) {
         id = sdsdup(id);
     }
     de = dictFind(server.cluster->nodes_black_list,id);
-    dictSetUnsignedIntegerVal(de,time(NULL));
+    dictSetUnsignedIntegerVal(de,time(NULL)+REDIS_CLUSTER_BLACKLIST_TTL);
     sdsfree(id);
 }