Handle StandalonePods Succeeded case when checking status

[Y--]

Description
When Skaffold checks a standalone pod's status (method checkStandalonePodsStatus) , it currently only considers Failed and Running state, any other status will lead the pod to be systematically added to the pendingPods collection.

According to the documentation, a pod can be in 5 different states: Pending, Running, Succeeded, Failed or Unknown.

While it make sense for Pending or Unknown pods to be added to the pendingPods collection, I think it does not for the Succeeded ones (pods that terminated successfully)

This PR introduces a tiny change which just skips Succeeded pods.

Tests

I tried to look at other test and could only find:

• unit tests on CheckStatus that don't involve StandalonePods resource
• TestPollServiceStatus, TestPollJobStatus, TestPollDeployment, none of which involve StandalonePods resource

Please let me know if I've missed it, I'd be happy to add test on it.

Thanks!

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[mattsanta]

Thanks for the PR!

So the current behavior is that status checking does not work if the Pod has completed and has a Succeeded phase, skaffold will continue to poll the Pod status until it times out. I also went ahead and tested your fix by building skaffold locally and it looks like it works.

I know the current tests don't ever use StandalonePods, but could you be the first one to add a test case that does for this scenario?