Fix LargeSet.exists().
Fix LargeSet.exists().

pradeepsrinivasan/aerospike-client-java,wgpshashank/aerospike-client-java,alexandrnikitin/aerospike-client-java,alexandrnikitin/aerospike-client-java,pradeepsrinivasan/aerospike-client-java,wgpshashank/aerospike-client-java