feat: Add functional test for update agent [ORBP-573]

[alekseifedotov]

In this PR I'm adding integration test for update agent.

How it works

The script spawns a podman container with update-agent inside. That docker container partially reproduces orb environment. It mocks:

• efivars
• /usr/persistent/
• /dev/mmcblk0 (sdcard).
• /etc/orb_update_agent.conf
• claim.json

In claim.json it contains links on local files to get the update.
After update-agent is done, the script compares the resulting partitions with the expected ones.

Future steps

• generate OTA files on startup
• integrate the test in the CI
• add localstack to mock S3 buckets
• add dbus in the container to mock dbus communication
• add mcu emulation
• add capsule update mock

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I'll make it a draft for now.

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Requirements:

• nu shell
• libguestfs
• podman

[vmenge]

this is awesome and I think a great start for us in feeling safe with update-agent changes 🥳

what I'd ask here is to as a next step (on a separate PR) move this over to something that can be used with both cargo watch and cargo test for a quick feedback loop when iterating locally 🙏

[alekseifedotov]

what I'd ask here is to as a next step (on a separate PR) move this over to something that can be used with both cargo watch and cargo test for a quick feedback loop when iterating locally 🙏

The test itself takes a couple of minutes, so I don't think it is suitable to run in cargo watch