Add stack persistent volume claim

[pmorillon]

Description

A proposal to fix #42 like PR #63, taking into account the new method to download Hook artifacts with a Job (previously with an init container). PVC accessModes are checked to disable hook downloader Job and inform user when ReadWriteOnce is used (default to ReadWriteMany).

Why is this needed

Fixes: #42

How Has This Been Tested?

Only tested with ReadWriteOnce PVC. Checked generated manifests with helm install --debug --dry-run...

How are existing users impacted? What migration steps/scripts do we need?

Actual default behavior should be preserved

Checklist:

I have:

• [ ] updated the documentation and/or roadmap (if required)
• [ ] added unit or e2e tests
• [ ] provided instructions on how to upgrade

[jacobweinstock]

Hey @pmorillon , thanks for this. Looks good. Just going to run a few test scenarios locally and then we'll merge it.

[pmorillon]

I took into account all your comments in the last commit

[chrisdoherty4]

Thank you, this is awesome.

[jacobweinstock]

Looks like this branch needs a rebase of main.

[mddeff]

@chrisdoherty4 @jacobweinstock

I came to this PR after following #42 and #63 while in search of a solution for hook that didnt use hostPath. It looks like we (and by we, I mean @pmorillon) were SO close to getting this merged.

If the final code-comment you requested is added and re-base complete, can we get this merged? Using hostPath could be considered a blocker to running Tinkerbell in many production environments.

I love what the Tinkerbell project is doing, awesome stuff!