change the order of TOC

Author: sl-solution

docs/src/index.md

@@ -17,10 +17,10 @@ Pages = ["man/basics.md",
          "man/formats.md",
          "man/map.md",
          "man/byrow.md",
+         "man/modify.md",
          "man/filter.md",
          "man/sorting.md",
          "man/grouping.md",
-         "man/modify.md",
          "man/aggregation",
          "man/transpose.md",
          "man/joins.md"]