[vpr][CLI] set skip_sync default value to false

Author: amin1377

vpr/src/base/read_options.cpp

@@ -3098,7 +3098,9 @@ argparse::ArgumentParser create_arg_parser(const std::string& prog_name, t_optio
     analysis_grp.add_argument<bool, ParseOnOff>(args.skip_sync_clustering_and_routing_results, "--skip_sync_clustering_and_routing_results")
         .help(
             "Select to skip the synchronization on clustering results based on routing optimization results."
-            "Note that when this sync-up is disabled, clustering results may be wrong (leading to incorrect bitstreams)!");
+            "Note that when this sync-up is disabled, clustering results may be wrong (leading to incorrect bitstreams)!")
+        .default_value("off")
+        .show_in(argparse::ShowIn::HELP_ONLY);
 
     analysis_grp.add_argument<bool, ParseOnOff>(args.generate_net_timing_report, "--generate_net_timing_report")
         .help(