dr-autosync: add configuration description

Signed-off-by: disksing <[email protected]>

two-data-centers-in-one-city-deployment.md

@@ -221,6 +221,7 @@ The replication mode is controlled by PD. You can configure the replication mode
     primary-replicas = 3
     dr-replicas = 2
     wait-store-timeout = "1m"
+    wait-recover-timeout = "0s"
     ```
 
 - Method 2: If you have deployed a cluster, use pd-ctl commands to modify the configurations of PD.
@@ -243,6 +244,7 @@ Descriptions of configuration items:
 + `primary-replicas` is the number of Voter replicas in the primary AZ.
 + `dr-replicas` is the number of Voter replicas in the disaster recovery AZ.
 + `wait-store-timeout` is the waiting time for switching to asynchronous replication mode when network isolation or failure occurs. If the time of network failure exceeds the waiting time, asynchronous replication mode is enabled. The default waiting time is 60 seconds.
++ `wait-recover-timeout` is the waiting time for switching back to the `sync-recover` status after the network recovers. The default value is 0 seconds.
 
 To check the current replication status of the cluster, use the following API: