fix: Allow specifying root volume in block device mappings

[luohao]

Fixes #3962

Description

• Karpenter doesn't support specifying root volumes within block device mappings. This update introduces a RootVolume flag to the BlockDeviceMapping, enabling Karpenter to utilize the configured volume size for pod packing.

How was this change tested?
Unit tests.

Does this change impact docs?

• Yes, PR includes docs updates
• Yes, issue opened: #
• No

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

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[bwagner5]

Chatted on slack. Will join community meeting Aug 31 to discuss

[github-actions]

This PR has been inactive for 14 days. StaleBot will close this stale PR after 14 more days of inactivity.

[jonathan-innis]

We'll have to make sure to add the conversion logic for the v1beta1 APIs when this feature goes in.

[luohao]

We'll have to make sure to add the conversion logic for the v1beta1 APIs when this feature goes in.

Hi Jonathan, I didn't see provider in v1beta1 directory. Can you point me to the API or the conversion code?

[jonathan-innis]

We'll have to make sure to add the conversion logic for the v1beta1 APIs when this feature goes in.

Hi Jonathan, I didn't see provider in v1beta1 directory. Can you point me to the API or the conversion code?

You'll have to rebase. I think that this branch is based off an older commit so the v1beta1 changes are not in there yet. I'm also fine to just apply these changes to the v1beta1 APIs rather than supporting both v1alpha1 and v1beta1. This is going to be the place for all of our new features going forward so it might make sense for this to just go there if the conversion changes are too much. Happy to help in any way that's useful with this! Feel free to reach out to me on Slack!

[jonathan-innis]

Nice! LGTM 🚀

[jonathan-innis]

/karpenter snapshot

[github-actions]

Snapshot successfully published to oci://public.ecr.aws/karpenter/karpenter:v0-50c365bf3788cc399613e69d527a9ef5de960ec8. Find the image tag and installation instructions at https://gallery.ecr.aws/karpenter/karpenter/