err tmp file name should en with gz to satify ucking writer

src/collection/flowcells.rs

@@ -177,7 +177,7 @@ impl FlowCells {
         //     .truncate(true)
         //     .open(archive_path)
         //     .with_context(|| format!("Failed to open archive file for writing: {archive_path}"))?;
-        let tmp_path = format!("/tmp/{}.tmp", uuid::Uuid::new_v4());
+        let tmp_path = format!("/tmp/{}.json.gz", uuid::Uuid::new_v4());
 
         let mut file = get_gz_writer(&tmp_path, true)
             .with_context(|| format!("Failed to open archive file for writing: {archive_path}"))?;