Fix: Update Zabbix API connector to handle versioning for 'with_hosts' parameter (#2049)

This changes the version number for `with_hosts` to return `real_hosts`
when version is 6.0.0 or below.

In 6.2 `real_hosts` is deprecated.
https://www.zabbix.com/documentation/6.2/en/manual/api/reference/hostgroup/get

In 6.0 it isn't.
https://www.zabbix.com/documentation/6.0/en/manual/api/reference/hostgroup/get

Fixes https://github.com/grafana/grafana-zabbix/issues/2048

.changeset/gentle-suits-invite.md

@@ -0,0 +1,5 @@
+---
+'grafana-zabbix': patch
+---
+
+Fix: `real_hosts` deprecated in version 6.2 and 6.4