No network access required for fully cached query

[gordonwatts]

User should not need to connect to the internet when accessing a fully cached/downloaded query.

• Example: when you create the dataset, it queries for the code-gen backends

[kyungeonchoi]

We need a test for this

[BenGalewsky]

This should be the case. Let's verify and see if we can close this

[ponyisi]

Added a test, verified code passes (#439 )