Change default filename to match relayd(8) 'keypair' expectation (.crt):

Index: acme-client.conf
===================================================================
RCS file: /cvs/src/etc/examples/acme-client.conf,v
retrieving revision 1.5
diff -u -p -u -p -r1.5 acme-client.conf
--- acme-client.conf	10 May 2023 07:34:57 -0000	1.5
+++ acme-client.conf	27 Jul 2025 20:51:29 -0000
@@ -26,7 +26,7 @@ authority buypass-test {
 domain example.com {
 	alternative names { secure.example.com }
 	domain key "/etc/ssl/private/example.com.key"
-	domain full chain certificate "/etc/ssl/example.com.fullchain.pem"
+	domain full chain certificate "/etc/ssl/example.com.crt"
 	# Test with the staging server to avoid aggressive rate-limiting.
 	#sign with letsencrypt-staging
 	sign with letsencrypt