message: Clarify lint error message.
diff: @@ -150,7 +150,7 @@ std::string UndersizedBinaryLiteralRule::FormatReason(
  break;
  }
  return absl::StrCat(base_describe, " literal ", width, base_text, literal,
  - " is shorter than its declared width: ", width, ".");
  + " has less digits than expected for ", width, " bits.");
  }
  absl::Status UndersizedBinaryLiteralRule::Configure(
  