Bitnami post update after changes in their catalog (#360)

### Description

This posts adds a noticed that the post for the bitnami helm chart is
out of date. I opted to add a notice instead of deleting so readers
could be directed to work on the replacement.
 
### Issues Resolved

#355

### Check List
- [x] Commits are signed per the DCO using `--signoff`

By submitting this pull request, I confirm that my contribution is made
under the terms of the BSD-3-Clause License.

---------

Signed-off-by: Kyle J. Davis <kyledvs@amazon.com>

Author: stockholmux

content/blog/2024-06-27-using-bitnami-valkey-chart/index.md

@@ -12,6 +12,8 @@ featured_image = "/assets/media/featured/random-01.webp"
 
 +++
 
+> **Due to changes in the [Bitnami catalog](https://github.com/bitnami/charts/issues/35164)**, the contents of this blog post are, as of September 2025, likely out-of-date and the helm chart **does not represent an operational best practice** without a subscription. This post is preserved for historical reference only. You can track work towards a project-provided Helm chart at [valkey-io/valkey#2371](https://github.com/valkey-io/valkey/issues/2371).
+
 Valkey is a high-performance key/value datastore that supports workloads such as caching, and message queues, supporting many data types including strings, numbers, hashes, bitmaps, and more. Valkey can run in standalone or cluster mode for replication and high availability.
 
 [Bitnami](https://bitnami.com/) offers a number of secure, up-to-date, and easy to deploy charts for a number of popular open source applications.