[DigitalOcean] droplet integration

[asaiacai]

This adds digital ocean droplets to the sky.

Tested (run the relevant ones):

• Code formatting: bash format.sh
• All smoke tests: pytest tests/test_smoke.py --do

[moinnadeem]

@asaiacai I would be really interested in using this work -- do you know when you might be able to land this PR?

[asaiacai]

Hello! I’m aiming for this to land in next two weeks providing testing goes smoothly. Stay tuned!

[asaiacai]

@Michaelvll i think this PR is finally ready, once you have a free moment! I've currently disabled tests for gpu droplets as they are still in early access, but I think I got the remaining tests to work on normal CPU droplets fine. Let me know if you find any issues.

[asaiacai]

also this catalog update is required to pass the sky serve requests since I added cheaper 2vcpu instances.

skypilot-org/skypilot-catalog#83

[cblmemo]

Thanks for this amazing work @asaiacai ! This would be very helpful. Left some discussions ;)

[asaiacai]

@cblmemo reran smoke, but if you have a moment to review again, thanks in advance!

[asaiacai]

@cblmemo digital ocean released a new image for AI/ML with docker. It's a lot more bloated than the ubuntu-22.04 images that were previously used for the CPU VMs but it does ship with docker, and i've removed the docker wait. please let me know if you need anything else for this PR.

[cblmemo]

Thanks @asaiacai for this amazing contribution! Looks mostly good to me. After those nits get resolved and smoke test passed, it should be ready to go!

[cblmemo]

Is it possible to reuse the previous function and add another argument for accelerator to use? same for other tests in this file. You can checkout @pytest.mark.parametrize