Use non-default service account for pre-hook Jobs

[bradyz7]

What would you like Teleport to do?
The pods created by the auth pre-deploy job and proxy pre-deploy job use the default service account. Instead, the pods should respect the service account set in serviceAccount.name

What problem does this solve?
This is similar to #21421 for the test jobs in teleport-cluster using the default service account

If a workaround exists, please include it.
No, we don't have a workaround at the moment

[zmb3]

Duplicate of #21384?

[bradyz7]

Duplicate of #21384?

Not exactly, it seems #21384 is to have the option for the proxy service account to have a different name besides {{- coalesce .Values.serviceAccount.name .Release.Name -}}-proxy, while the ask here is to be able to set an alternative service account for the auth and proxy pre-deploy jobs at all.