exempt ScalaFiddle from link checking (#1296)

Author: SethTisue

.github/workflows/ci.yaml

@@ -29,4 +29,4 @@ jobs:
       - name: Proofing (Cron)
         if: ${{ github.event_name == 'schedule' }}
         run: |
-          bundle exec htmlproofer ./_site/ --external_only --only-4xx --http-status-ignore "400,401,429" --empty-alt-ignore --allow-hash-href --url-ignore "/trends.google.com/,/pgp.mit.edu/,/www.oracle.com/"
+          bundle exec htmlproofer ./_site/ --external_only --only-4xx --http-status-ignore "400,401,429" --empty-alt-ignore --allow-hash-href --url-ignore "/trends.google.com/,/pgp.mit.edu/,/www.oracle.com/,/scalafiddle.io/"

_posts/2015-02-05-scala-js-no-longer-experimental.md

@@ -153,7 +153,7 @@ There are three main ways to get started with Scala.js:
 
 * [The tutorial](https://www.scala-js.org/doc/tutorial.html)
 * The free e-book [Hands-on Scala.js](https://lihaoyi.github.io/hands-on-scala-js/)
-* The online sandbox [Scala.jsFiddle](http://www.scala-js-fiddle.com/)
+* The online sandbox [ScalaFiddle](https://scalafiddle.io)
 
 So go ahead!
 Use it, love it, and build the web applications of the future!