[core] Fix checkstyle for Client (#918)
[core] Fix checkstyle for Client (#918)


manolama/YCSB,madhurihn/YCSB_ToyDB,ChristianNavolskyi/YCSB,manolama/YCSB,cricket007/YCSB,madhurihn/YCSB_ToyDB,leschekhomann/YCSB,ChristianNavolskyi/YCSB,jaemyoun/YCSB,madhurihn/YCSB_ToyDB,leschekhomann/YCSB,jaemyoun/YCSB,jaemyoun/YCSB,madhurihn/YCSB_ToyDB,zyguan/ycsb,brianfrankcooper/YCSB,leschekhomann/YCSB,jaemyoun/YCSB,manolama/YCSB,cricket007/YCSB,cricket007/YCSB,zyguan/ycsb,manolama/YCSB,leschekhomann/YCSB,cricket007/YCSB,brianfrankcooper/YCSB,ChristianNavolskyi/YCSB,zyguan/ycsb,ChristianNavolskyi/YCSB,brianfrankcooper/YCSB,zyguan/ycsb,brianfrankcooper/YCSB