[k8s] Increase ssh timeout when calling uptime

[romilbhardwaj]

Issue

When trying provisioning on a Kubernetes cluster on a high latency connection (e.g., different geographic region + VPN), SkyPilot would get stuck on launching. This is because the uptime call run by the ray autoscaler to check for cluster liveness uses a very short ConnectTimeout=5s. Using a larger SSH timeout fixes the issue.

Fix in this PR

This PR introduces a monkey patch to SSHCommandRunner in kubernetes/node_provider.py. It uses a larger timeout when running uptime to check cluster liveness. This monkeypatch to SSHCommandRunner.runis necessary since the ray autoscaler sets the timeout on a per-call basis (as an arg to SSHCommandRunner.run) and the 5s timeout is hardcoded in updater.py::NodeUpdater.wait_ready() is hard to modify without duplicating a large chunk of ray autoscaler code.

Thus, we monkey patch the run method to check if the command being run is 'uptime', and if so change the timeout to 10s.

Tested (run the relevant ones):

• Code formatting: bash format.sh
• sky launch -c test --cloud kubernetes on GKE and EKS clusters on a high latency connection.

[landscapepainter]

Confirmed it runs successfully to launch k8s instance. LGTM!