CRITICAL alert when ports are unbound

This bug report is of the same essence as #2004210

When a port is created within a project, but not attached to a device, nagios reports a CRITICAL alert.

$ /usr/local/lib/nagios/plugins/check_resources.py port --all
CRITICAL: ports 1/3 are DOWN, 2/3 passed

$ openstack port show test -f yaml
admin_state_up: true
allowed_address_pairs: []
binding_host_id: ''
binding_profile: {}
binding_vif_details: {}
binding_vif_type: unbound
binding_vnic_type: normal
created_at: '2023-05-29T14:27:03Z'
data_plane_status: null
description: ''
device_id: ''
device_owner: ''
dns_assignment:
- fqdn: host-192-168-21-194.mytest.stsstack.qa.1ss.
  hostname: host-192-168-21-194
  ip_address: 192.168.21.194
dns_domain: ''
dns_name: ''
extra_dhcp_opts: []
fixed_ips:
- ip_address: 192.168.21.194
  subnet_id: 84430095-f1e4-4c4e-9edb-1205e463f937
id: 2ac8713e-ee59-4a3f-8251-a5430c16c66a
ip_allocation: immediate
location:
  cloud: ''
  project:
    domain_id: 3dbad36fa7c94764b336ff36ea9c94f5
    domain_name: null
    id: 2cfb0895647a4026864dbf125bc75b03
    name: admin
  region_name: ''
  zone: null
mac_address: fa:16:3e:a7:7b:1e
name: test
network_id: 188bf901-812a-4a55-8932-264b35eb23c6
port_security_enabled: true
project_id: 2cfb0895647a4026864dbf125bc75b03
propagate_uplink_status: null
qos_network_policy_id: null
qos_policy_id: null
resource_request: null
revision_number: 1
security_group_ids:
- 7abcd68d-d860-45b6-8a4f-d40b93a87fcf
status: DOWN
tags: []
trunk_details: null
updated_at: '2023-05-29T14:27:03Z'

If there is an unbound port, a DOWN status should not be a critical alert. Maybe a WARNING or even INFO but definitely not CRITICAL.