update korro

Author: koperagen

docs/StardustDocs/topics/convert.md

@@ -57,7 +57,7 @@ enum class Direction { NORTH, SOUTH, WEST, EAST }
 
 ```kotlin
 dataFrameOf("direction")("NORTH", "WEST")
-   .convert("direction").to<Direction>()
+    .convert("direction").to<Direction>()
 ```
 
 <!---END-->

docs/StardustDocs/topics/groupByConcat.md

@@ -1,4 +1,4 @@
-[//]: # (title: Group/concat rows)
+[//]: # (title: GroupBy/concat rows)
 
 * [`groupBy`](groupBy.md) — groups rows of `DataFrame` by given key columns
 * [`concat`](concat.md) — concatenates rows from several `DataFrames` into single `DataFrame`