chore: clear allow dead_code for flat format

Signed-off-by: evenyag <realevenyag@gmail.com>

src/mito2/src/memtable/bulk.rs

@@ -243,7 +243,6 @@ pub struct BulkMemtable {
     max_sequence: AtomicU64,
     num_rows: AtomicUsize,
     /// Cached flat SST arrow schema for memtable compaction.
-    #[allow(dead_code)]
     flat_arrow_schema: SchemaRef,
     /// Compactor for merging bulk parts
     compactor: Arc<Mutex<MemtableCompactor>>,
@@ -637,7 +636,6 @@ impl IterBuilder for BulkRangeIterBuilder {
 
 /// Iterator builder for encoded bulk range
 struct EncodedBulkRangeIterBuilder {
-    #[allow(dead_code)]
     file_id: FileId,
     part: EncodedBulkPart,
     context: Arc<BulkIterContext>,
@@ -679,7 +677,6 @@ impl IterBuilder for EncodedBulkRangeIterBuilder {
 struct BulkPartWrapper {
     part: BulkPart,
     /// The unique file id for this part in memtable.
-    #[allow(dead_code)]
     file_id: FileId,
     /// Whether this part is currently being merged.
     merging: bool,
@@ -688,7 +685,6 @@ struct BulkPartWrapper {
 struct EncodedPartWrapper {
     part: EncodedBulkPart,
     /// The unique file id for this part in memtable.
-    #[allow(dead_code)]
     file_id: FileId,
     /// Whether this part is currently being merged.
     merging: bool,

src/mito2/src/read/flat_projection.rs

@@ -39,7 +39,6 @@ use crate::sst::{
 ///
 /// This mapper support duplicate and unsorted projection indices.
 /// The output schema is determined by the projection indices.
-#[allow(dead_code)]
 pub struct FlatProjectionMapper {
     /// Metadata of the region.
     metadata: RegionMetadataRef,

src/mito2/src/read/scan_util.rs

@@ -657,7 +657,6 @@ pub(crate) fn scan_mem_ranges(
 }
 
 /// Scans memtable ranges at `index` using flat format that returns RecordBatch.
-#[allow(dead_code)]
 pub(crate) fn scan_flat_mem_ranges(
     stream_ctx: Arc<StreamContext>,
     part_metrics: PartitionMetrics,
@@ -709,7 +708,6 @@ pub(crate) async fn scan_file_ranges(
 }
 
 /// Scans file ranges at `index` using flat reader that returns RecordBatch.
-#[allow(dead_code)]
 pub(crate) async fn scan_flat_file_ranges(
     stream_ctx: Arc<StreamContext>,
     part_metrics: PartitionMetrics,
@@ -851,7 +849,6 @@ pub(crate) async fn maybe_scan_other_ranges(
     }
 }
 
-#[allow(dead_code)]
 pub(crate) async fn maybe_scan_flat_other_ranges(
     context: &Arc<StreamContext>,
     index: RowGroupIndex,