apache chain issue fix

installation/pleroma-apache.conf

@@ -32,9 +32,8 @@ CustomLog ${APACHE_LOG_DIR}/access.log combined
 
 <VirtualHost *:443>
     SSLEngine on
-    SSLCertificateFile      /etc/letsencrypt/live/${servername}/cert.pem
+    SSLCertificateFile      /etc/letsencrypt/live/${servername}/fullchain.pem
     SSLCertificateKeyFile   /etc/letsencrypt/live/${servername}/privkey.pem
-    SSLCertificateChainFile /etc/letsencrypt/live/${servername}/fullchain.pem
 
     # Mozilla modern configuration, tweak to your needs
     SSLProtocol             all -SSLv3 -TLSv1 -TLSv1.1