Since 4.0.0 there is a field proxy_address for limiting proxy requests.
Official Docs: "Proxy address If specified then active proxy requests are only accepted from this list of comma-delimited IP addresses, optionally in CIDR notation, or DNS names of active Zabbix proxy.
This field is only available if an active proxy is selected in the Proxy mode field. Macros are not supported.
This option is supported since Zabbix 4.0.0."
updated documentation/help
fixed test issues
fixed version_added not a string
fix suggestions by D3DeFi
added changelog fragment
applied D3DeFi suggestions
way cleaner and better readable
