fix(typography): enable iOS long-press context menus

- for links, this allows a range of options to be selected
- for apps that want to disable this to pretend that they are
  native mobile apps, they can set the `-webkit-touch-callout: none;`
  style on their app's `html, body`

Fixes #10622

Author: Splaktar

src/core/style/typography.scss

@@ -7,7 +7,7 @@
 
 html, body {
   -webkit-tap-highlight-color: rgba(0,0,0,0);
-  -webkit-touch-callout: none;
+  -webkit-touch-callout: default;
 
   min-height: 100%; // [2]