feat(db): Enable running postgres locally in prod-mode

[crankynetman]

This lets you run prod with a local postgres instance. We prolly need to document the vault stuff, but I think that's better suited for #88 to handle.

I think this MR is ready to rock, it's deployed and working on scram-pentest.ocean.cu-es.net presently.

[github-actions]

File	Coverage
All files	81%	✅
config/consumers.py	71%	✅
config/urls.py	69%	✅
config/settings/base.py	70%	✅
config/settings/local.py	72%	✅
scram/route_manager/models.py	70%	✅
scram/route_manager/views.py	78%	✅
scram/route_manager/api/serializers.py	73%	✅
scram/route_manager/api/views.py	83%	✅
scram/templates/403.html	91%	✅
scram/templates/404.html	91%	✅
scram/templates/base.html	99%	✅

Minimum allowed coverage is 50%

Generated by 🐒 cobertura-action against 8d82a54

[samoehlert]

looks great!