debian buster: root and alias conflict

[t-b]

Here on nginx of debian buster I had to remove the root directive as nginx complained.

The working setup to be included in a server directive is:

        # BEGIN BACKUPPC
        location /backuppc {
                allow 127.0.0.1/32;
                allow 192.168.100.0/24;
                deny all;

                access_log  /var/log/nginx/backuppc.access.log;
                error_log   /var/log/nginx/backuppc.error.log;

                auth_basic "BackupPC";
                auth_basic_user_file /etc/backuppc/htpasswd;

                alias /usr/share/backuppc/cgi-bin/;
                index /index.cgi;

                if ($scheme = http) {
                        return 301 https://$server_name$request_uri;
                }
        }

        location ~\.cgi$ {
                gzip off;
                include /etc/nginx/fastcgi_params;
                fastcgi_pass unix:/run/fcgiwrap.socket;
                fastcgi_index BackupPC_Admin;
                fastcgi_param SCRIPT_FILENAME /usr/share/backuppc/cgi-bin$fastcgi_script_name;
        }
        # END BACKUPPC