Fixes #4: Resolved 502 Bad Gateway error by updating docker-compose.yml

[GaneshN523]

Summary:

This pull request fixes Issue #4, where the Nginx reverse proxy was returning a 502 Bad Gateway error due to FastAPI services not being ready before startup.

Changes Made:

• Health Checks: Added pg_isready health checks for movie_db and cast_db to ensure they are available before dependent services start.
• Updated depends_on Behavior: Now waits for database readiness instead of just container startup.
• Restart Policies: Set restart: always for all services to improve reliability.
• Fixed Volume Issue: Corrected postgres_data_cast volume declaration.
• Ensured Proper Networking: Verified service-to-service communication within the Docker network.

How to Test:

1. Rebuild and start containers:

   docker-compose up --build -d