message: docs: 0 disables route timeout
  Calling out that it's possible to use the value 0 to disable route timeout (as it is for idle timeout).
diff: @@ -562,7 +562,8 @@ message RouteAction {
  // Specifies the upstream timeout for the route. If not specified, the default is 15s. This
  // spans between the point at which the entire downstream request (i.e. end-of-stream) has been
  - // processed and when the upstream response has been completely processed.
  + // processed and when the upstream response has been completely processed. A value of 0 will
  + // disable the route's timeout.
  //
  // .. note::
  //
  