Port to azd env get value

[pamelafox]

Purpose

This ports to azd env get-value, which will be in a future azd release.
Azure/azure-dev#4080

Does this introduce a breaking change?

When developers merge from main and run the server, azd up, or azd deploy, will this produce an error?
If you're not sure, try it out on an old environment.

[ ] Yes
[X] No

Type of change

[ ] Bugfix
[ ] Feature
[X] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[ ] Other... Please describe:

Code quality checklist

See CONTRIBUTING.md for more details.

• The current tests all pass (python -m pytest).
• I added tests that prove my fix is effective or that my feature works
• I ran python -m pytest --cov to verify 100% coverage of added lines
• I ran python -m mypy to check for type errors
• I either used the pre-commit hooks or ran ruff manually on my code.

[john0isaac]

@pamelafox before you merge remove echo=True from the engine creation
The logs are full of sqlalchmey logs

rag-postgres-openai-python/src/backend/fastapi_app/postgres_engine.py

Line 33 in bba4c88

echo=True,

[pamelafox]

Lol I kind of love those logs, its like the Matrix, but good point, I think I accidentally turned that to True in a recent branch. Turning to False.