🌱 Add Ignore rollout status

[dhaiducek]

Summary

An Ignore rollout status in my reading of it felt different than a Skip status, where Ignore would mean that it wouldn't factor into a rollout but would receive updates while Skip would mean it didn't receive updates, but I'm open to discussion on it.

I also have an optional commit here to add RolloutType to make the enum a bit more concrete.

Related issue(s)

• rollout helper functions #254

[dhaiducek]

/cc @mprahl

[openshift-ci]

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[qiujian16]

/assign @haoqing0110

[haoqing0110]

For the skip status, when adding it, expect it to be a status return from ClusterRolloutStatusFunc by API consumers, indicating that the consumers do not want to do a rollout on this cluster.
For the ignore status, not sure what does "receive updates" mean? in the PR seems ingore returns the same value as skip.

[dhaiducek]

/hold

For the skip status, when adding it, expect it to be a status return from ClusterRolloutStatusFunc by API consumers, indicating that the consumers do not want to do a rollout on this cluster. For the ignore status, not sure what does "receive updates" mean? in the PR seems ingore returns the same value as skip.

Thanks for the feedback. We want users to be able to specify that a particular cluster should get updated in the rollout but it doesn't matter to them whether the status is returned successful. It seems adding Ignore is confusing, so we're going to consider this further. For this it seems like we should just use Succeeded if it succeeds but add a FailedNonBlocking status instead of Ignore to say that the library is aware it failed during the rollout but is continuing on.