lets encryptの箇所修正

infra/nginx/default.conf

@@ -8,7 +8,7 @@ server {
     return 301 https://$host$request_uri;
 
 	# SSL化
-	ssl_certificate /etc/letsencrypt/live/kikikan.xyz/cert.pem;
+	ssl_certificate /etc/letsencrypt/live/kikikan.xyz/fullchain.pem;
 	ssl_certificate_key /etc/letsencrypt/live/kikikan.xyz/privkey.pem;
 
 	access_log /var/log/nginx/ssl-access.log;