Merge branch 'dev-README-update-with-postgres-system-config' into 'dev'

README: add info about system postgresql configuration

See merge request !403
4 jobs for dev in 44 minutes and 11 seconds (queued for 57 seconds)
Status Job ID Name Coverage
  Cabal
passed #17910
cabal

00:20:43

 
  Stack
passed #17911
stack

00:02:57

 
  Bench
manual #17912
allowed to fail manual
bench
 
  Test
passed #17913
test

00:20:30