[TD-3944]<fix>: make default offline threshold to 10 days. (#5912)

Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

packaging/cfg/taos.cfg

@@ -64,7 +64,7 @@
 # monitorInterval           30
 
 # number of seconds allowed for a dnode to be offline, for cluster only 
-# offlineThreshold          8640000
+# offlineThreshold          864000
 
 # RPC re-try timer, millisecond
 # rpcTimer                  300

src/common/src/tglobal.c

@@ -139,7 +139,7 @@ int32_t tsTableIncStepPerVnode = TSDB_TABLES_STEP;
 int8_t  tsEnableBalance = 1;
 int8_t  tsAlternativeRole = 0;
 int32_t tsBalanceInterval = 300;           // seconds
-int32_t tsOfflineThreshold = 86400 * 100;  // seconds 100 days
+int32_t tsOfflineThreshold = 86400 * 10;  // seconds of 10 days
 int32_t tsMnodeEqualVnodeNum = 4;
 int8_t  tsEnableFlowCtrl = 1;
 int8_t  tsEnableSlaveQuery = 1;