netpol: fix duplicate default drop acl

[zhangzujian]

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

What type of this PR

• Bug fixes

Which issue(s) this PR fixes:

E0911 06:23:53.500514       1 ovn-nb-acl.go:599] more than one acl with same 'parent np.1.kube.system direction from-lport priority 2000 match inport == @np.1.kube.system && ip4'
E0911 06:23:53.500571       1 network_policy.go:500] failed to set egress acl log for np kube-system/np-1, more than one acl with same 'parent np.1.kube.system direction from-lport priority 2000 match inport == @np.1.kube.system && ip4'

WHAT

🤖 Generated by Copilot at 8b3a751

Fix a bug that caused unnecessary default drop rules for network policies with no ports or selectors. Refactor the address set name format and update the unit tests accordingly. Improve the performance and readability of the ACL allow rules functions.

🤖 Generated by Copilot at 8b3a751

There once was a bug in the code
That made default drop rules explode
But with nil and a suffix
The logic got fixed
And the network policies flowed

HOW

🤖 Generated by Copilot at 8b3a751

• Avoid creating duplicate default drop rules for port groups when network policy has no pod or namespace selector (link, link)
• Replace empty slice with nil for port argument in UpdateIngressACLOps and UpdateEgressACLOps functions (link, link)
• Update test cases for UpdateIngressACLOps and UpdateEgressACLOps functions (link, link, link, link)