Merge pull request #15758 from dotty-staging/backport-15645

Backport #15645: deprecate ToString type which should be deprecated at 3.2.0

Author: Kordyjan

library/src/scala/compiletime/ops/int.scala

@@ -244,7 +244,7 @@ object int:
    *  ```
    *  @syntax markdown
    */
-  //@deprecated("Use compiletime.ops.any.ToString instead.","3.2.0") // uncomment when reaching 3.2.0
+  @deprecated("Use compiletime.ops.any.ToString instead.","3.2.0")
   type ToString[X <: Int] <: String
 
   /** Long conversion of an `Int` singleton type.