doc: auto_host_rewrite works with STATIC clusters if hostname is provided (#23248)

Update documentation to indicate that auto_host_rewrite works with STATIC clusters, provided that the hostname attribute of the endpoint is configured.

Signed-off-by: Klearchos Chaloulos <chaloulo@nokia.com>

Mirrored from https://github.com/envoyproxy/envoy @ 6d293a901a51f46289ef2b5491c248d93b974d81

envoy/api/v2/route/route_components.proto

@@ -859,8 +859,9 @@ message RouteAction {
     // Indicates that during forwarding, the host header will be swapped with
     // the hostname of the upstream host chosen by the cluster manager. This
     // option is applicable only when the destination cluster for a route is of
-    // type *strict_dns* or *logical_dns*. Setting this to true with other cluster
-    // types has no effect.
+    // type ``STRICT_DNS``,  ``LOGICAL_DNS`` or ``STATIC``. For ``STATIC`` clusters, the
+    // hostname attribute of the endpoint must be configured. Setting this to true
+    // with other cluster types has no effect.
     google.protobuf.BoolValue auto_host_rewrite = 7;
 
     // Indicates that during forwarding, the host header will be swapped with the content of given