fix deleting old sb chassis for a re-added node

[zhangzujian]

• Make sure you have followed Kube-OVN Code Style.

What type of this PR

• Bug fixes

Which issue(s) this PR fixes:

I0627 07:27:07.575182       7 node.go:594] handle update node ubuntu-1
W0627 07:27:07.583831       7 ovn-sbctl.go:46] ovn-sbctl command error: ovn-sbctl --timeout=60 --db=tcp:[172.16.70.140]:6642 set chassis c4ef0754-8d6a-433b-ad55-8a15a0ce330c external_ids:vendor=kube-ovn external_ids:node=ubuntu-1 in 8ms
E0627 07:27:07.583882       7 node.go:617] failed to set chassis nodeTag for node 'ubuntu-1', failed to set chassis external_ids, ovn-sbctl: no row "c4ef0754-8d6a-433b-ad55-8a15a0ce330c" in table Chassis
, "exit status 1"
E0627 07:27:07.583926       7 node.go:155] error syncing 'ubuntu-1': failed to set chassis external_ids, ovn-sbctl: no row "c4ef0754-8d6a-433b-ad55-8a15a0ce330c" in table Chassis
, "exit status 1", requeuing

WHAT

🤖 Generated by Copilot at 5fbb74c

Refine chassis management and validation in ovn-sbctl.go and node.go. This improves the efficiency and reliability of node status updates and network connectivity.

🤖 Generated by Copilot at 5fbb74c

Sing, O Muse, of the mighty deeds of the ovn-kubernetes team
Who strive to fix the network woes of the nodes and pods supreme
They refactor and refine the code with skill and diligence
To validate and set the chassis nodeTag with elegance

HOW

🤖 Generated by Copilot at 5fbb74c

• Refactor the logic of validating and setting the chassis nodeTag for a node into a separate function validateChassis (link)
• Simplify the logic of deleting the chassis by node name by calling GetChassis and DeleteChassisByName functions (link)
• Swap the order of the ovn-sb commands in the GetChassis function to use the node name as the external_id first, and then the hostname (link)