Create Serving_a_different_domain.md

The location directive was missing the "=" operator.

Running-Mastodon/Serving_a_different_domain.md

@@ -67,7 +67,7 @@ Therefore, the easiest way to configure domain.org is to redirect `/.well-known/
 With nginx, it would be as simple as adding:
 
 ```nginx
-location /.well-known/host-meta {
+location = /.well-known/host-meta {
        return 301 https://social.example.org$request_uri;
 }
 ```