[BUG] Node import failed with distributed server in Core Xml!

[jhonzy0928]

Describe the bug
I was trying to deploy the distributed node, and when I had the distributed service deployed, I tried to save the XML file, but when I re-opened the Xml file a second time, the assigned server on the node disappeared and became a normal node. This causes me to need to reassign servers to nodes, which is annoying if the number of nodes grows.
To Reproduce
Steps to reproduce the behavior:

1. Deploy distributed scenarios
2. Assign a slave server to a node
3. Run, and then save the file after running successfully
4. After the file is imported again, the distributed node becomes a common node

Expected behavior
In the Xml file, the node has the server: field, and the server to which the file node is assigned should not change

Screenshots

Desktop (please complete the following information):

• OS: [e.g. Ubuntu 22.04]
• CORE Version [e.g. 9.0.3]
• EMANE Version [e.g. 1.5.1]

Additional context
I would appreciate it if you could solve my problem。