Fix a couple of links to the docs

Author: gurdiga

upgrade-docs/0.19.md

@@ -55,7 +55,7 @@ Both are quite similar to the `elm-package.json` format, and `elm-upgrade` can h
 
 - `String.toInt : String -> Maybe Int` (not `Result` anymore)
 - `String.toFloat : String -> Maybe Float` (not `Result` anymore)
-- `Basics.toString` becomes [`Debug.toString`](https://package.elm-lang.org/packages/elm/core/latest/Debug#toString), [`String.fromInt`](https://package.elm-lang.org/packages/elm/core/latest/String#toInt), and [`String.fromFloat`](https://package.elm-lang.org/packages/elm/core/latest/String#toFloat).
+- `Basics.toString` becomes [`Debug.toString`](https://package.elm-lang.org/packages/elm/core/latest/Debug#toString), [`String.fromInt`](https://package.elm-lang.org/packages/elm/core/latest/String#fromInt), and [`String.fromFloat`](https://package.elm-lang.org/packages/elm/core/latest/String#fromFloat).
 - `Basics.rem 451 10` becomes [`remainderBy 10 451`](https://package.elm-lang.org/packages/elm/core/latest/Basics#remainderBy)
 - `451 % 10` becomes [`modBy 10 451`](https://package.elm-lang.org/packages/elm/core/latest/Basics#modBy)
 - `style : List (String, String) -> Attribute msg` becomes `String -> String -> Attribute msg`
@@ -159,4 +159,4 @@ They are still able to define that function, but it will need a human readable n
 
 ## Notes:
 
-- `toString` — A relatively common bug was to show an `Int` in the UI, and then later that value changes to something else. `toString` would just show wrong information until someone noticed. The new `String.fromInt` and `String.fromFloat` ensure that cannot happen. Furthermore, more elaborate types almost certainly need localization or internationalization, which should be handled differently anyway.
+- `toString` — A relatively common bug was to show an `Int` in the UI, and then later that value changes to something else. `toString` would just show wrong information until someone noticed. The new `String.fromInt` and `String.fromFloat` ensure that cannot happen. Furthermore, more elaborate types almost certainly need localization or internationalization, which should be handled differently anyway.