message: Change panic message in `send_request` of unit tests slightly
diff: @@ -222,8 +222,7 @@ impl<REv: 'static> ComponentHarness<REv> {
  self.runtime.block_on(receiver).unwrap_or_else(|err| {
  // The channel should never be closed, ever.
  panic!(
  - "request for {} channel closed with error \"{}\", this is a serious bug --- \
  - a component will likely be stuck from now on",
  + "request for {} channel closed with error \"{}\" in unit test harness",
  err,
  type_name::<T>()
  );
  