Fix org name in Helm chart's imageEnvoy description

Update the description for the Helm chart's connectInject.imageEnvoy
parameter to reflect the correct organization name for images published by
EnvoyProxy.io.

website/source/docs/platform/k8s/helm.html.md

@@ -295,7 +295,7 @@ to run the sync program.
 
   * <a name="v-connectinject-imageConsul" href="#v-connectinject-imageConsul">`imageConsul`</a> (`string: global.image`) - The name of the Docker image (including any tag) for Consul. This is used for proxy service registration, Envoy configuration, etc.
 
-  * <a name="v-connectinject-imageEnvoy" href="#v-connectinject-imageEnvoy">`imageEnvoy`</a> (`string: ""`) - The name of the Docker image (including any tag) for the Envoy sidecar. `envoy` must be on the executable path within this image. This Envoy version must be compatible with the Consul version used by the injector. This defaults to letting the injector choose the Envoy image, which is usually `envoy/envoy-alpine`.
+  * <a name="v-connectinject-imageEnvoy" href="#v-connectinject-imageEnvoy">`imageEnvoy`</a> (`string: ""`) - The name of the Docker image (including any tag) for the Envoy sidecar. `envoy` must be on the executable path within this image. This Envoy version must be compatible with the Consul version used by the injector. This defaults to letting the injector choose the Envoy image, which is usually `envoyproxy/envoy-alpine`.
 
   * <a name="v-connectinject-namespaceselector" href="#v-connectinject-namespaceselector">`namespaceSelector`</a> (`string: ""`) - A [selector](https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/) for restricting injection to only matching namespaces. By default all namespaces except `kube-system` and `kube-public` will have injection enabled.