ci: wait for terminating ovs-ovn pod to disappear

[zhangzujian]

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

What type of this PR

Examples of user facing changes:

• Features
• Bug fixes
• Docs
• Tests

Which issue(s) this PR fixes:

Waiting for daemon set "ovs-ovn" rollout to finish: 1 out of 2 new pods have been updated...
daemon set "ovs-ovn" successfully rolled out
Collecting ovn logging files
Error from server (NotFound): pods "ovs-ovn-pt4ll" not found
Error: Process completed with exit code 1.

WHAT

🤖 Generated by Copilot at b7aa3ab

Improve the reliability of the build-x86-image workflow by using a better method to wait for ovs-ovn daemonset readiness. Change the pod counting logic in .github/workflows/build-x86-image.yaml.

🤖 Generated by Copilot at b7aa3ab

ovs-ovn waits
counting pods, not endpoints
more stable workflow

HOW

🤖 Generated by Copilot at b7aa3ab

• Modify the condition for waiting for the ovs-ovn daemonset to be ready in four jobs in the workflow (link, link, link, link). Use the number of ovs pods and nodes instead of the ovn-nb endpoint, which may not be available in some environments.