ipam: fix ippool with single dual-stack address

[zhangzujian]

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

What type of this PR

• Bug fixes

Which issue(s) this PR fixes:

Fixes #3050

WHAT

🤖 Generated by Copilot at 345c2bf

This pull request enhances the ipPool annotation feature for pods and statefulsets, and increases the timeout-minutes for some GitHub workflow jobs. It fixes a bug in the pod controller's acquireAddress function, adds more test cases for the ipPool annotation in the test/e2e/kube-ovn/ipam/ipam.go file, and adjusts the .github/workflows/build-x86-image.yaml and .github/workflows/scheduled-e2e.yaml files to prevent timeout failures.

🤖 Generated by Copilot at 345c2bf

Oh we are the kube-ovn crew and we have a job to do
We build and test the image and we push it to the hub
We tweak the timeouts and the tests to make them run just right
And we fix the ipPool bug and add a new feature tonight

HOW

🤖 Generated by Copilot at 345c2bf

• Increase the timeout-minutes for the GitHub workflow jobs that build the x86 image and run the conformance tests (link, link)
• Fix a bug that causes pod address allocation to fail when the ipPool annotation has mixed protocols (link)
• Support the use case where the ipPool annotation specifies a single IP address instead of a range or a list (link)
• Modify the test case for the ipPool annotation in the test/e2e/kube-ovn/ipam/ipam.go file to cover different numbers of replicas and delete the statefulset after each iteration (link)