Fix some hint message based on review comments.

saidump/SaiDump.cpp

@@ -31,7 +31,7 @@ void SaiDump::printUsage()
     std::cout << "    -g --dumpGraph:" << std::endl;
     std::cout << "        Dump current graph" << std::endl;
     std::cout << "    -r --rdb:" << std::endl;
-    std::cout << "        Dump by parsing the RDB JSON file, which is created based on Redis dump.rdb that is generated by Redis SAVE command" << std::endl;
+    std::cout << "        Dump by parsing the RDB JSON file, which is created based on Redis dump.rdb that is generated by redis-cli --rdb command" << std::endl;
     std::cout << "    -m --max:" << std::endl;
     std::cout << "        Config the the RDB JSON file's max size in MB, which is optional with default value 100MB" << std::endl;
     std::cout << "    -h --help:" << std::endl;

syncd/scripts/saidump.sh

@@ -11,7 +11,6 @@ import json
 with open('$filepath') as json_file:
   data = json.load(json_file)
   print(data['INSTANCES']['redis']['hostname'], data['INSTANCES']['redis']['port'], data['INSTANCES']['redis']['unix_socket_path'])
-  json_file.close()")
 
   # split
   redis_config=(${redis_config// / })
@@ -26,7 +25,7 @@ with open('$filepath') as json_file:
   logger "saidump.sh: [2] Run rdb-cli command to convert the dump files into JSON files."
   rdb-cli $redis_dir/dump.rdb json | tee $redis_dir/dump.json > /dev/null
 
-  logger "saidump.sh: [3] Run saidump -r to update the JSON files' format as same as the saidump before. Then we can get the saidump's result in standard output."
+  logger "saidump.sh: [3] Run saidump -r to get the result at standard output from the JSON file."
   saidump -r $redis_dir/dump.json -m 100
 
   logger "saidump.sh: [4] Clear the temporary files."