DLPX-92333 Cherry-pick Delphix commits of grub2 for LTS upgrade

[palash-gandhi]

Problem

grub2’s focal and noble branches have differing histories making it impossible to merge them. Instead, we’ve chosen to pull in noble’s commits and cherry-picking Delphix commits on top of upstream.

The following commits need to be cherry-picked on to os-upgrade now that it tracks the applied/ubuntu/noble-updates branch of upstream:

1. DLPX-73603 Grub should always default to the kernel version that comes with the active Delphix version #10

Solution

1. Cherry-pick DLPX-73603 Grub should always default to the kernel version that comes with the active Delphix version #10. Then, apply the same changes to the version_sort function because it replaces the version_find_latest function

Testing Done

Built the package here: https://ops-jenkins.eng-tools-prd.aws.delphixcloud.com/job/linux-pkg/job/os-upgrade/job/build-package/job/grub2/job/pre-push/5/console

Open questions

1. How do I test this change without a 24.04 appliance? Is it okay to defer testing till we can build an appliance? We are operating on the "os-upgrade" branch anyway.
2. Which of these should also be cherry-picked?
   DLPX-80252 [Backport of DLPX-80189 to 6.0.14.0] grub-probe failed during upgrade of kdump-tools package #27
   DLPX-76797 grub-initrd-fallback.service fails on Ubuntu 20.04 #19
   DLPX-73688 Recovery environment is unreachable #12
3. I also found some PRs related to recovery-environment. Do we need them?