message: Add descriptive log for assert-generated fail
diff: @@ -32,5 +32,8 @@ const out = child_process
  if (out !== "") {
  console.error("Modified files:");
  console.error(out);
  + console.log();
  + console.log("To fix this run `node scripts/assert-generated` and commit the results");
  + console.log();
  process.exit(1);
  }
  