result: delete legacy Rows type

It is no longer needed. For compatibility with LegacyQueryResult and
LegacyRowIterator, higher-layer conversions suffice.

scylla-cql/src/frame/response/result.rs

@@ -793,16 +793,6 @@ impl<'frame> DeserializedMetadataAndRawRows<'frame, RawRowsBorrowed<'frame>> {
     }
 }
 
-#[derive(Debug)]
-pub struct Rows {
-    pub metadata: ResultMetadataHolder<'static>,
-    pub paging_state_response: PagingStateResponse,
-    pub rows_count: usize,
-    pub rows: Vec<Row>,
-    /// Original size of the serialized rows.
-    pub serialized_size: usize,
-}
-
 #[derive(Debug)]
 pub enum Result {
     Void,
@@ -1203,29 +1193,6 @@ impl RawMetadataAndRawRows {
         |cached| ResultMetadataHolder::SharedCached(Arc::clone(cached)),
         deser_col_specs_owned,
     );
-
-    pub fn into_legacy_rows(
-        self,
-        paging_state_response: PagingStateResponse,
-    ) -> StdResult<Rows, RowsParseError> {
-        let raw_rows_with_deserialized_metadata = self.deserialize_owned_metadata()?;
-
-        let rows_size = raw_rows_with_deserialized_metadata.rows_bytes_size();
-        let rows_count = raw_rows_with_deserialized_metadata.rows_count();
-        let rows = raw_rows_with_deserialized_metadata
-            .rows_iter::<Row>()?
-            .collect::<StdResult<_, _>>()?;
-
-        let metadata = raw_rows_with_deserialized_metadata.into_metadata();
-
-        Ok(Rows {
-            metadata,
-            paging_state_response,
-            rows_count,
-            rows,
-            serialized_size: rows_size,
-        })
-    }
 }
 
 fn deser_prepared_metadata(