♻️: make munin_client independant from server configuration

roles/munin_client/templates/munin-node.conf.j2

@@ -41,7 +41,7 @@ host_name {{ ansible_host }}
 # network notation unless the perl module Net::CIDR is installed.  You
 # may repeat the allow line as many times as you'd like
 
-allow ^{{ hostvars['munin']['ansible_default_ipv4']['address'].split('.')|join('\.') }}
+allow ^{{ hostvars['munin']['proxmox_net0']['ip'] | ansible.utils.ipaddr('address') | split('.') |join('\.') }}
 allow ^127\.0\.0\.1$
 allow ^::1$