Add rel="me" to profile website link

[smichaelsen]

Semantically it would be correct to give the website link on the profile page the rel="me" attribute.

https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/rel/me

Real life benefit: People could verify her Monkeytype profiles on Mastodon: https://mastodon.online/@smic

I took the freedom to create a PR: #4015

[flookey]

Completed with #4015