Update image family.

Author: dwsteele

.cirrus.yml

@@ -27,7 +27,7 @@ freebsd_14_task:
 # ----------------------------------------------------------------------------------------------------------------------------------
 freebsd_15_task:
   freebsd_instance:
-    image_family: freebsd-15-0
+    image_family: freebsd-15-0-amd64-ufs
     cpu: 4
     memory: 4G