message: logger: rename tx, rx -> sender, receiver
  Closes:
diff: @@ -80,14 +80,14 @@ impl LibraLoggerBuilder {
  pub fn build(&mut self) {
  let logger = if self.is_async {
  - let (tx, rx) = mpsc::sync_channel(self.channel_size);
  + let (sender, receiver) = mpsc::sync_channel(self.channel_size);
  let service = LoggerService {
  - rx,
  + receiver,
  address: self.address.clone(),
  printer: self.printer.take(),
  };
  let logger = Arc::new(LibraLogger {
  - tx: Some(tx),
  + sender: Some(sender),
  printer: None,
  level: self.level,
  });
  @@ -96,7 +96,7 @@ impl LibraLoggerBuilder {
  logger
  } else {
  Arc::new(LibraLogger {
  - tx: None,
  + sender: None,
  printer: self.printer.take(),
  level: self.level,
  })
  @@ -109,7 +109,7 @@ impl LibraLoggerBuilder {
  }
  pub struct LibraLogger {
  - tx: Option<SyncSender<StructuredLogEntry>>,
  + sender: Option<SyncSender<StructuredLogEntry>>,
  printer: Option<Box<dyn Writer>>,
  level: Level,
  }
  @@ -141,8 +141,8 @@ impl LibraLogger {
  printer.write(s);
  }
  - if let Some(tx) = &self.tx {
  - if let Err(e) = tx.try_send(entry) {
  + if let Some(sender) = &self.sender {
  + if let Err(e) = sender.try_send(entry) {
  STRUCT_LOG_QUEUE_ERROR_COUNT.inc();
  eprintln!("Failed to send structured log: {}", e);
  }
  @@ -185,7 +185,7 @@ impl crate::struct_log::StructLogSink for Arc<LibraLogger> {
  }
  struct LoggerService {
  - rx: Receiver<StructuredLogEntry>,
  + receiver: Receiver<StructuredLogEntry>,
  address: Option<String>,
  printer: Option<Box<dyn Writer>>,
  }
  @@ -194,7 +194,7 @@ impl LoggerService {
  pub fn run(mut self) {
  let mut writer = self.address.take().map(TcpWriter::new);
  - for entry in self.rx {
  + for entry in self.receiver {
  PROCESSED_STRUCT_LOG_COUNT.inc();
  if let Some(writer) = &mut writer {
  