Zabbix

..F.....S. [DEV-3729] fixed information exposure in System information widget for users without proper permissions

Merge in ZBX/zabbix from feature/DEV-3729-6.0 to release/6.0

* commit '1a80276771240c344acc5c9c67f8b43b69232c9c':
  ........S. [DEV-3729] removed unused variable
  ........S. [DEV-3729] fixed status.get response to return empty data for non super administrator user
  ..F....... [DEV-3729] fixed code style; updated server data retrieval to be available only for super admins
  ..F....... [DEV-3729] fixed information exposure in System information widget for users without proper permissions