Add proper preview bounds to checkpoint blog post

Author: pedro-psb

docs/sections/blog/posts/2025/checkpoint.md

@@ -16,6 +16,8 @@ Inspired by the success stories of [Ubuntu Snapshots on Azure](https://ubuntu.co
 [increased security and resiliency of Canonical workloads on Azure](https://techcommunity.microsoft.com/blog/linuxandopensourceblog/increased-security-and-resiliency-of-canonical-workloads-on-azure---now-in-previ/3970623), we
 embarked on a journey to develop a feature that could address these challenges.
 
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 ## The Problem
 
 Imagine working on a project where you need to ensure that your deployment environment is consistent