fix typo

Signed-off-by: Ruihang Xia <[email protected]>

src/metric-engine/src/engine.rs

@@ -818,7 +818,7 @@ impl MetricEngineInner {
         Ok(())
     }
 
-    /// Perform metric engine specific logic to incomming rows.
+    /// Perform metric engine specific logic to incoming rows.
     /// - Change the semantic type of tag columns to field
     /// - Add table_id column
     /// - Generate tsid