helm chart: allow setting resources on the cleanup job/hook

[dmaes]

Summary

• Add .Values.cleanup.resources: {} value to allow setting resources on the cleanup hook job

Checklist

For Helm Chart changes

• [ ] Categorize the PR by setting a good title and adding one of the labels: bug, enhancement, documentation, change, breaking, dependency as they show up in the changelog
• [ ] PR contains the label area:chart
• [ ] PR contains the chart label, e.g. chart:k8up
• [x] Commits are signed off
• [x] Variables are documented in the values.yaml using the format required by Helm-Docs.
• [ ] Chart Version bumped if immediate release after merging is planned
• [x] I have run make chart-docs
• [ ] Link this PR to related code release or other issues.