subnet: update status after deleting IP CR

[zhangzujian]

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

What type of this PR

• Bug fixes
• Tests

Which issue(s) this PR fixes:

Fixes #(issue-number)

WHAT

🤖 Generated by Copilot at f9a4ee3

This pull request enhances the garbage collection and status update of logical switch ports and IP custom resources in the kube-ovn controller. It also adds a new e2e test case to verify the subnet status updates in the underlay network.

🤖 Generated by Copilot at f9a4ee3

We're sailing on the kube-ovn net, oh aye, oh aye
We're cleaning up the ports and IPs, oh aye, oh aye
We're using subnet as a key, to update the status easily
And we're testing it with IPv6, oh aye, oh aye

HOW

🤖 Generated by Copilot at f9a4ee3

• Add a new variable subnet to store the subnet name of the lsp in markAndCleanLSP and query the IP CR to get the subnet name (link, link)
• Enqueue the subnet name to the updateSubnetStatusQueue after marking and cleaning the lsp, deleting the IP CR, or releasing the address for the port (link, link, link)
• Simplify the code in syncKubeOvnNet by assigning the subnet object to a variable (link)
• Add a new function waitSubnetStatusUpdate to the underlay package to wait for the subnet status fields to match the expected values (link)
• Call the waitSubnetStatusUpdate function in the TestUnderlayIPAM test case to verify the subnet status updates after creating and deleting pods with different subnets and IP versions (link, link, link, link, link, link, link, link, link)