certbot-compat: remove dupe random25863 nginx name (#8286)

random25863.example.org appears in multiple port 80 virtualhosts in the
nginx testdata tarball and also is in the nginx-roundtrip-testdata.
Certbot doesn't handle these properly, which results in random test
failures.

This commit ensures that random25863.example.org only appears in a
single virtualhost and should ensure that the tests pass consistently.

certbot-compatibility-test/nginx/nginx-roundtrip-testdata/79-configs/site-11849

@@ -30,7 +30,6 @@ server {
     server_name www.random3140.example.org;
     server_name random28398.example.org;
     server_name random23689.example.org www.random23689.example.org;
-    server_name random25863.example.org www.random25863.example.org;
 
     rewrite ^ http://random3140.example.org$request_uri permanent;
 }