[libcxx][ranges] Add `ranges::iter_swap`.

Differential Revision: https://reviews.llvm.org/D102809

NOKEYCHECK=True
GitOrigin-RevId: 40d6d2c49dd16641a6fd40916e1cc9a58513ed15
diff --git a/include/module.modulemap b/include/module.modulemap
index a49769b..de3daf8 100644
--- a/include/module.modulemap
+++ b/include/module.modulemap
@@ -455,6 +455,7 @@
       module default_sentinel     { header "__iterator/default_sentinel.h"     }
       module incrementable_traits { header "__iterator/incrementable_traits.h" }
       module iter_move            { header "__iterator/iter_move.h"            }
+      module iter_swap            { header "__iterator/iter_swap.h"            }
       module iterator_traits      { header "__iterator/iterator_traits.h"      }
       module next                 { header "__iterator/next.h"                 }
       module prev                 { header "__iterator/prev.h"                 }