Reuse an existing TLS CA from a previous installation

[siegfriedweber]

Until SDP 24.3, the SecretClass tls used the default namespace to store the TLS CA. In #397, the namespace was changed to the operator's namespace in the Helm installation. This is a breaking change and users migrating from a prior SDP version must either revert this change by setting the Helm value secretClasses.tls.caSecretNamespace to default or by copying the Secret secret-provisioner-tls-ca to the operator's namespace.

This change was already implemented and released in the OLM version 24.4.0 (see stackabletech/stackable-utils#65).

It was planned to just add a note to the changelog. But it turned out, that this manual step is error-prone and should be performed automatically.

One solution is to add a Job to the Helm installation which checks if the secret exists in the default namespace but not in the one set in caSecretNamespace and copies the secret in this case.