Fully use custom domain

[spydon]

I think it should be a pretty easy fix to fully use the https://ubuntufluttercommunity.org/ domain and not just redirect to the github pages default url like it does now. :)

https://docs.github.com/en/pages/configuring-a-custom-domain-for-your-github-pages-site/managing-a-custom-domain-for-your-github-pages-site