zabbix_agentd: Update to 7.0.18 (LTS)

zabbix_agentd: Update to 7.0.18 (LTS)

- Update of rootfile not required

Bugs fixed:
- ZBX-26723	Fixed Zabbix Agent active remote command getting timeout applied due to incorrect parsing of JSON
- ZBX-26697	Fixed memory error in sender when trying to read invalid response
- ZBX-26477	Fixed vfs.dir.get ignoring entries with 0 unixtime and fixed vfs.file.get having null values for time fields in this case
- ZBX-26143	Fixed duplicated address issue after redirection and disabled history upload on Agent connection failure until the connection is re-established

Full changelogs:
- https://www.zabbix.com/rn/rn7.0.17
- https://www.zabbix.com/rn/rn7.0.18
- https://www.zabbix.com/rn/rn7.0.10
- https://www.zabbix.com/rn/rn7.0.11

Signed-off-by: Robin Roevens <robin.roevens@disroot.org>
Reviewed-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>