fix: close the writer instead of merely dropping it

src/user_data.rs

@@ -171,6 +171,9 @@ pub enum UpdateError {
 
     /// couldn't write (modified) data for this user to the storage operator
     WriteError { source: std::io::Error },
+
+    /// couldn't finalize writing (modified) data for this user to the storage operator
+    FinalizeError { source: std::io::Error },
 }
 
 impl UserDataManager {
@@ -239,6 +242,8 @@ impl UserDataManager {
             .await
             .context(update_error::WriteSnafu)?;
 
+        decompressed_writer.close().await.context(update_error::FinalizeSnafu)?;
+
         Ok(ret)
     }
 }