chore(parquet): remove unnecessary mut row_group_writer_factory assig…

…nments

parquet/benches/arrow_writer.rs

@@ -348,7 +348,7 @@ fn write_batch_with_option(
         .with_coerce_types(props.coerce_types())
         .convert(batch.schema_ref())?;
     let writer = SerializedFileWriter::new(&mut file, parquet_schema.root_schema_ptr(), props)?;
-    let mut row_group_writer_factory = ArrowRowGroupWriterFactory::new(&writer, batch.schema());
+    let row_group_writer_factory = ArrowRowGroupWriterFactory::new(&writer, batch.schema());
 
     bench.iter(|| {
         let mut row_group = row_group_writer_factory.create_column_writers(0).unwrap();

parquet/tests/encryption/encryption_async.rs

@@ -548,7 +548,7 @@ fn spawn_rg_join_and_finalize_task(
 }
 
 fn spawn_parquet_parallel_serialization_task(
-    mut writer_factory: ArrowRowGroupWriterFactory,
+    writer_factory: ArrowRowGroupWriterFactory,
     mut data: Receiver<RecordBatch>,
     serialize_tx: Sender<JoinHandle<RBStreamSerializeResult>>,
     schema: Arc<Schema>,
@@ -778,7 +778,7 @@ async fn test_multi_threaded_encrypted_writing() {
     let temp_file = tempfile::tempfile().unwrap();
     let mut writer =
         SerializedFileWriter::new(&temp_file, parquet_schema.root_schema_ptr(), props).unwrap();
-    let mut row_group_writer_factory =
+    let row_group_writer_factory =
         ArrowRowGroupWriterFactory::new(&writer, Arc::clone(&schema));
 
     let (serialize_tx, mut serialize_rx) =