Update postgres version from 9.5 to 10 of external database

Hey there,

I want to update my manageiq appliance from hammer to ivanchuk. So I installed a new appliance with the ivanchuk image. Now I am trying to connect the new appliance to my existing external database where hammer with postgres version 9.5 is running.
The evm.log file shows an error message that says

The version of PostgreSQL being connected to is incompatible with ManageIQ (10 required) (RuntimeError)

How can I update the postgres version of my existing database instance?

Regards
Moritz