BYO PKI: Help address situations in which first HSM gets replaced before initalization

[ckamps]

HSMs can end up being replaced by AWS due to internal failures and other circumstances. When the first HSM in a cluster gets replaced prior to the cluster being initialized, the cluster private key and consequently the CSR are also replaced. This means that the external/BYO PKI process needs to be restarted to use the new CSR. The longer the BYO PKI process takes, the greater exposure of the initial HSM to being replaced.

This issue calls for the IaC to be enhanced to help minimize the impact of this situation.