Allow the addition of a ServiceAccount to the PrePuller

[samyuh]

Proposed change

The current daemonset configuration does not permit the specification of a ServiceAccount.

Alternative options

One alternative is to allow the assignment of a custom label. However, this is not an ideal solution because our goal is for all pods to have an associated ServiceAccount.

Who would use this feature?

This feature is necessary for everyone who want to deploy pods with a ServiceAccount.

[samyuh]

You can check the file regarding this daemonset here: https://github.com/jupyterhub/zero-to-jupyterhub-k8s/blob/main/jupyterhub/templates/image-puller/_helpers-daemonset.tpl

[samyuh]

Fixed this issue on the following pull request: #3441

Can someone take a look? @minrk

[samyuh]

I will close this issue since this is more likely a bug