... and remove some weirdnesses.
- Port to Python
- Drop the extra pkgs, config, system args
- Drop all `with`
- Don't override the standard PostgreSQL directory
- Use pkgs and lib from the test runner
Tested with:
- postgresql_12
- postgresql_11
- postgresql_10
- postgresql_9_6
- postgresql_9_5
Closes#96347
cc @flokli