chore: PG version upgrade in docker-compose

[k3yss]

[openoms]

The postgres upgrade has also faiiled on charts testflight https://github.com/GaloyMoney/charts/pull/7538 :

k -n bria-testflight-a1b4894 logs  bria-6f97456c99-qswcg
Defaulted container "bria" out of: bria, wait-for-postgresql (init)
Sending traces to http://localhost:4317
Starting server processes
Error: while executing migration 20210316025847: error returned from database: function uuid_nil() does not exist

Caused by:
    0: error returned from database: function uuid_nil() does not exist
    1: function uuid_nil() does not exist