Update kubernetes.mdx (#10871)
Update kubernetes.mdx (#10871)

Add suggestion to validate K8S cluster address and TCP port using cluster-info command and update sample config (line 77) to prompt for validation. Feedback from prospect was that doc is misleading since our sample uses TCP 8443.
hartsock/vault,hashicorp/vault,rnaveiras/vault,rnaveiras/vault,hashicorp/vault,hartsock/vault,hashicorp/vault,hartsock/vault,hashicorp/vault,rnaveiras/vault,hartsock/vault,rnaveiras/vault,hashicorp/vault,rnaveiras/vault,hashicorp/vault,hartsock/vault