[libcxx][ranges] Add `counted_iterator`.

Differential Revision: https://reviews.llvm.org/D106205

NOKEYCHECK=True
GitOrigin-RevId: 8a48e6dda9f7fb9c7ae7207dcb9570d2c11255ad
diff --git a/include/module.modulemap b/include/module.modulemap
index 11cabad..b5781b0 100644
--- a/include/module.modulemap
+++ b/include/module.modulemap
@@ -485,6 +485,7 @@
       module back_insert_iterator  { private header "__iterator/back_insert_iterator.h" }
       module common_iterator       { private header "__iterator/common_iterator.h" }
       module concepts              { private header "__iterator/concepts.h" }
+      module counted_iterator      { private header "__iterator/counted_iterator.h" }
       module data                  { private header "__iterator/data.h" }
       module default_sentinel      { private header "__iterator/default_sentinel.h" }
       module distance              { private header "__iterator/distance.h" }