IotDB cluster is not using FQDN as seed node address

In a k8s environment, when you restart a multinode iotdb server instances, instances try to connect to IPs of old instances.

I am using FQDN addresses in seed nodes list but as far as I understand, IotDB changes them to IP addresses and store them as IP addresses.

**To Reproduce**
Steps to reproduce the behavior:
1. Start 3 instances of IotDB server in k8s environment, (seed nodes list must contain FQDNs)
2. Restart all instances.
3. See logs to see IotDB tries to connect to IP address of the first run.

**Expected behavior**
IotDB should store FQDNs and convert them to IPs at startup or when first used.

**Kubernetes Environment**
- IotDB 0.12.3

Reproduce el problema con tres instancias de IoTDB 0.12.3 en Kubernetes y nodos seed FQDN; después, inspecciona los logs del reinicio y rastrea dónde se persisten las direcciones seed. Se considera terminado cuando las instancias reiniciadas conservan los FQDN y los resuelven a las IP actuales durante el arranque o el primer uso, en lugar de reconectarse a direcciones IP antiguas.

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