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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
If we're going to be unstable, let's go all the way.
This change was motivated by needing to upgrade cargo-machete to make it
work with Rust v1.77, and not having the upgrade in nixos-unstable.
V3_GIT_ORIGIN_REV_ID: 8191a376a6aeebc08787f973d58d373f8ab9ad0d
I got frustrated by the lack of useful output when services failed to
start in CI, so I thought I'd mess around.
I made some changes so that:
1. we wait for services with health checks to report as healthy,
2. we do not rebuild the engine or custom connector when they start,
3. the health checks work (apart from ndc-postgres, which will come
later), and
4. we use environment variables rather than command-line arguments where
possible.
I have also renamed the "agent" binary to "custom-connector", matching
its crate, because it was driving me a little crazy.
V3_GIT_ORIGIN_REV_ID: 8d672b0b25438b54d47368ce82cd236cfdd4e554
