Reorder cleanup step by put subnet and vpc to the last to avoid conflict

[oilbeater]

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

What type of this PR

Examples of user facing changes:

• Bug fixes

Which issue(s) this PR fixes:

Fixes #(issue-number)

WHAT

copilot:summary

copilot:poem

HOW

copilot:walkthrough

[github-actions]

• The cleanup script should be refactored to group resources by type and delete them in a more efficient way. For example, all subnets could be deleted at once instead of looping through each one individually.
• There is a potential bug in the script where the "set +e" command is not followed by a corresponding "set -e" command, which could cause errors to be ignored and not properly handled.
• It would be helpful to add comments to the script to explain what each section is doing and why certain resources are being deleted in a specific order.
• The script could benefit from error handling and logging to better track any issues that may arise during the cleanup process.
• It may be useful to add a confirmation prompt before deleting resources to prevent accidental deletions.