Update nginx.config.sample to exclude php5-fpm

M2.2.x is not compatible with php5.x so there's no reason to include it as an option in the nginx.config.sample

Author: Sean Breeden

nginx.conf.sample

@@ -3,7 +3,6 @@
 #    # use tcp connection
 #    # server  127.0.0.1:9000;
 #    # or socket
-#    server   unix:/var/run/php5-fpm.sock;
 #    server   unix:/var/run/php/php7.0-fpm.sock;
 # }
 # server {