Non-indicative error when running on a Completed pod

[eyalb181]

Bug Description

When running on a Pod with state=Completed, we get a non-informative error as can be seen in the logs. We need to detect that the pod is in a running state, and if it isn't, display a more helpful error.

Steps to Reproduce

Run mirrord with IMPERSONATED_POD_NAME=<name of a pod with state=Completed)

Backtrace

No response

Relevant Logs

❯ mirrord exec -c --steal --pod-namespace some-namespace --pod-name some-pod ./bin/main
thread '<unnamed>' panicked at 'unexpected response - expected env vars response None', mirrord-layer/src/lib.rs:407:13
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
fatal runtime error: failed to initiate panic, error 5
[1]    60108 abort      mirrord exec -c --steal --pod-namespace some-namespace --pod-name  ./bin/main

Your operating system and version

MacOS

Local process

Go

Local process version

No response

Additional Info

No response