[stable/msysql] deprecating chart (#24363)

Signed-off-by: Matt Farina <matt@mattfarina.com>

stable/mysql/Chart.yaml

@@ -1,8 +1,8 @@
 apiVersion: v1
 name: mysql
-version: 1.6.8
+version: 1.6.9
 appVersion: 5.7.30
-description: Fast, reliable, scalable, and easy to use open-source relational database
+description: DEPRECATED - Fast, reliable, scalable, and easy to use open-source relational database
   system.
 keywords:
 - mysql
@@ -13,9 +13,5 @@ icon: https://www.mysql.com/common/logos/logo-mysql-170x115.png
 sources:
 - https://github.com/kubernetes/charts
 - https://github.com/docker-library/mysql
-maintainers:
-- name: olemarkus
-  email: o.with@sportradar.com
-- name: viglesiasce
-  email: viglesias@google.com
+deprecated: true
 engine: gotpl

stable/mysql/OWNERS

@@ -1,4 +0,0 @@
-approvers:
-- olemarkus
-reviewers:
-- olemarkus

stable/mysql/README.md

@@ -7,6 +7,10 @@ For more information, see the Helm Charts [Deprecation and Archive Notice](https
 
 [MySQL](https://MySQL.org) is one of the most popular database servers in the world. Notable users include Wikipedia, Facebook and Google.
 
+## DEPRECATION NOTICE
+
+This chart is deprecated and no longer supported.
+
 ## Introduction
 
 This chart bootstraps a single node MySQL deployment on a [Kubernetes](http://kubernetes.io) cluster using the [Helm](https://helm.sh) package manager.