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## Description
In order to test things quicker, we'd like to be able to build custom
connector and friends in Nix, and then use the containers when running
tests. First step here is to be able to build Docker containers in Nix,
and add a CI job to ensure it still works.
Then we'll move onto publishing and using these images.
No-op build times:
<img width="336" alt="Screenshot 2024-04-25 at 15 53 56"
src="https://github.com/hasura/v3-engine/assets/4729125/47cbc0c5-6e54-4583-aa01-0528d4a21080">
Functional no-op.
V3_GIT_ORIGIN_REV_ID: 8f9d609e26cdd3b0801e61fd361c241ad504dcdf
