Upgrade to lastest postgres version RDS supports

[depombo]

it looks like the docker registry itself failed to return the postgres container https://github.com/iasql/iasql-engine/runs/8092665190?check_suite_focus=true#step:6:18 I wonder if lesser-used containers run into these problems? We're using Postgresql 13.4 in our test suite but 14.5 is the latest release I am pretty sure 13.4 was the latest RDS supported last year. We could update the Docker compose yaml to 14.5, validate it still works (don't see why not) and then schedule a DB upgrade in staging and then production?