Need something better than .Release.IsUpgrade in conditional dependencies
We use .Release.IsUpgrade as a criteria in dependency computation to cover cases where a dependency needs to be added on an update but does not apply to the initial deployment of the cluster (e.g. here.
This .Release.IsUpgrade isn't an excellent criteria: when false, we know that the workload cluster does not exist yet, but we can have scenario (failure in choosing values, retries) where .Release.IsUpgrade would be true but the workload cluster would not exist yet.
We need to improve that (we could have cluster-machines-ready produce a dummy flag ConfigMap when the cluster becomes ready, and have the depends on conditioned base on a successful lookup of this ConfigMap).