Spec: firewall integration uses correct port

[aramprice]

  [FAILED] Expected
      <string>: Chain PREROUTING (policy ACCEPT)
      target     prot opt source               destination         
      
      Chain INPUT (policy ACCEPT)
      target     prot opt source               destination         
      
      Chain FORWARD (policy ACCEPT)
      target     prot opt source               destination         
      
      Chain OUTPUT (policy ACCEPT)
      target     prot opt source               destination         
      
      Chain POSTROUTING (policy ACCEPT)
      target     prot opt source               destination         
      
  to match regular expression
      <string>: ACCEPT *tcp *anywhere *2001:db8::1 *tcp dpt:http-alt cgroup 2958295042
  In [It] at: /tmp/build/22f0b5c7/bosh-agent/integration/nats_firewall_test.go:99 @ 02/25/26 23:57:24.752

^^^ https://ci.bosh-ecosystem.cf-app.com/teams/main/pipelines/bosh-agent-main/jobs/test-integration/builds/1092#L6991d2e9:171:195

[aramprice]

Likely superseded by #412

[aramprice]

Closing in favor of #412