Fix: Use os.environ.get to read configuration env vars to avoid issues during dev

app/config.py

@@ -25,4 +25,4 @@ class StagingConfig(BaseConfig):
 
 
 class ProductionConfig(BaseConfig):
-    SQLALCHEMY_DATABASE_URI = os.environ["DB_URL"]
+    SQLALCHEMY_DATABASE_URI = os.environ.get("DB_URL")