🐛 Fix the PostgreSQL Homebrew definition

[purinkle]

Before, we used the simple postgres alias to install PostgreSQL with Homebrew. Homebrew has removed this alias and needs us to define the required version. We fixed the definition to use the full formula name and define a version.

[nbibler]

I think brew install postgres now fails with recent versions of Homebrew and the install exits with errors:

Warning: No available formula with the name "postgres". Did you mean postgrest or postgis?
==> Searching for similarly named formulae...
These similarly named formulae were found:
check_postgres
postgresql@10
postgresql@11
postgresql@12
postgresql@13
postgresql@14
postgresql@9.4
postgresql@9.5
postgresql@9.6
postgrest
qt-postgresql
postgis
To install one of them, run (for example):
  brew install check_postgres
==> Searching for a previously deleted formula (in the last month)...
Error: No previously deleted formula found.
==> Searching taps on GitHub...
Error: No formulae found in taps.
Installing postgres has failed!
Homebrew Bundle failed! 1 Brewfile dependency failed to install.