Update index.mdx

Move @include 'kubernetes-supported-versions.mdx' to main k8s page rather than hidden in helm

Author: ram-parameswaran

content/vault/v1.18.x/content/docs/platform/k8s/index.mdx

@@ -40,6 +40,8 @@ to the Vault cluster which can be used to [store audit logs](/vault/docs/audit).
 native integrations provided by Vault itself, any other tool built for
 Kubernetes can choose to leverage Vault.
 
+@include 'kubernetes-supported-versions.mdx'
+
 ## Getting started with Vault and kubernetes
 
 There are several ways to try Vault with Kubernetes in different environments.