[helm chart] Support emptyDir type volume mounts

[onichandame]

What is your suggestion?

I'd like to create emptyDir type volumes and mount them to the main container.

Why do you want this feature?

The need for it arises from some setup tasks that are done by initContainers. For example, the apt mirror setup(/etc/apt/sources.list.d/debian.sources) can be brought in by an initContainer and transferred to the main container through a shared emptyDir volume.

Are there any workarounds to get this functionality today?

Host path type volumes can do, but they are too heavy for my use cases

Are you interested in submitting a PR for this?

Yes