Setting ignore=true to cluster with running deployments should be forbidden

[ayalash]

As a result of this bug, Platz server as deployments that can only be visible by API (because an ignored cluster is not part of any environment).

[ayalash]

The ignore attribute is used for both "is being managed by Platz" and for "is exist".
When a cluster is deleted from kubernetes we marked it as ignore, because it cannot be accessed anymore.

@popen2 Is it the desired behaivour?
Should Platz handle deleted cluster automatically?
Should the ignore attribute be split to 2 attributes?

[popen2]

The original intention of this flag was to ignore clusters that were detected by Platz but are not interesting to see in it.

ignore doesn't handle actual lifecycle operations like when a cluster is deleted while it has deployments in Platz (which IIUC is the case).

I don't think cluster deletion should be automatic, because Platz can lose access to a cluster due to permissions being revoked by accident and it's not great to just delete deployments in this case.

But -- clusters can be deleted once they have no deployments. Should this be solved with allowing deployments to be deleted without going through namespace deletion?