Fix name in comments

Author: odersky

library/src/scala/Conversion.scala

@@ -19,7 +19,7 @@ package scala
 *  from two to one.
 *
 *  The `Conversion` class can also be used to convert explicitly, using
-*  the `into` extension method.
+*  the `convert` extension method.
 */
 @java.lang.FunctionalInterface
 abstract class Conversion[-T, +U] extends Function1[T, U]:
@@ -28,5 +28,5 @@ abstract class Conversion[-T, +U] extends Function1[T, U]:
 object Conversion:
 
   extension [T](x: T)
-    /** `x.into[U]` converts a value `x` of type `T` to type `U` */
+    /** `x.convert[U]` converts a value `x` of type `T` to type `U` */
     def convert[U](using c: Conversion[T, U]) = c(x)