feat: Fix output block in ohpc-instance module for attaching multiple volumes

ohpc-instance/main.tf

@@ -80,5 +80,5 @@ output "ssh_host" {
 }
 
 output "device" {
-    value = openstack_compute_volume_attach_v2.volume_attach.device
+    value = openstack_compute_volume_attach_v2.volume_attach[count.index].device
 }