fix up the OpenVPN server role to use a consistent path for the CA

roles/OpenVPN-Server/vars/main.yml

@@ -2,6 +2,6 @@
 x509_csr_args: "--server"
 x509_cacert_file: "/etc/ssl/certs/ca.crt"
 x509_key_file: "/etc/ssl/private/server.key"
-x509_cert_file: "/etc/ssl/certs/server.pem"
+x509_cert_file: "/etc/ssl/certs/server.crt"
 x509_common_name: "{{ ansible_fqdn }}_OpenVPN_Server"
 dhparms_file: "/etc/ssl/private/dh.pem"