message: Include a NUL byte in the message returned by wasm_trap_message().
diff: @@ -38,7 +38,9 @@ pub unsafe extern "C" fn wasm_trap_message(
  out: &mut wasm_byte_vec_t,
  ) {
  let message = trap.inner.message();
  - let byte_vec: wasm_byte_vec_t = message.into_bytes().into();
  + let mut byte_vec = message.into_bytes();
  + byte_vec.push(0); // append NUL
  + let byte_vec: wasm_byte_vec_t = byte_vec.into();
  out.size = byte_vec.size;
  out.data = byte_vec.data;
  