Steps to reproduce:

1. Install PostgreSQL 12
2. Install zabbix agent2 5.0.1
3. Configure zbx_monitor account according to the instruction
4. Run from zabbix account: zabbix_agent2 -t "pgsql.archive[postgresql://127.0.0.1:5432,zbx_monitor,password,postgres]" -v

Result:
String in the output - ERROR: permission denied for function pg_ls_dir (SQLSTATE 42501).

Expected:
Instruction lacks necessary parameters (GRANTS) for zbx_monitor account.