Steps to reproduce:
On adding the following lines to `/etc/apt/sources.list.d/zabbix.list` and running `sudo apt update`, key verification fails
Lines added to `zabbix.list`:
On running `sudo apt update`:
Get:5 http:Err:5 http: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 082AB56BA14FE591
Reading package lists... Done
W: GPG error: http:E: The repository 'http: is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
To be able to install zabbix like any other package through `apt install`