fix: update old external links

Author: lorenzwalthert

_pkgdown.yaml

@@ -66,9 +66,9 @@ news:
     - text: "Version 1.2.0"
       href: https://www.tidyverse.org/blog/2019/11/styler-1-2-0/
     - text: "Version 1.3.0"
-      href: https://lorenzwalthert.netlify.com/post/styler-1-3-0/
+      href: https://lorenzwalthert.com/post/styler-1-3-0/
     - text: "Version 1.4.0"
-      href: https://lorenzwalthert.netlify.app/post/styler-1-4-0/
+      href: https://lorenzwalthert.com/post/styler-1-4-0/
 
 articles:
   - title: Get started