Update site_url to vanity domain

Author: hsoerensen

mkdocs.yml

@@ -1,7 +1,7 @@
 # yaml-language-server: $schema=https://squidfunk.github.io/mkdocs-material/schema.json
 site_name: Learn More
 site_description: Learn More about Voi
-site_url: https://voinetwork.github.io/learn-more/
+site_url: https://learn.voi.network/
 repo_url: https://github.com/VoiNetwork/learn-more
 edit_uri: edit/main/docs/