BUG: Remove unauthenticated MongoDB access — add credential support to MONGO_URI

[DewaldOosthuizen]

Summary

The docker-compose.yml sets MONGO_URI=mongodb://my_db:***@my_db:27017/.
3. Use the official mongo image (not an empty custom Dockerfile) so init env vars are respected.
4. Document the setup steps in README.

Acceptance Criteria

• my_db service requires credentials to connect
• MONGO_URI in docker-compose.yml includes auth credentials sourced from .env
• .env.example documents MONGO_USER and MONGO_PASSWORD
• README updated with credential setup instructions
• docker-compose up still starts cleanly with the new config

Complexity Estimate

S — requires adding env vars to compose file, updating .env.example, and adjusting README. No application code changes needed.

Priority

High — unauthenticated database access is a critical security misconfiguration.

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Auto-identified by workspace issue-logger
Category: CVE / security vulnerability
Complexity: S
Repository: DewaldOosthuizen/python_rest_tutorial