show devices diff should skip devices not in OPEN state

[denniswa]

snc@snc-lab> show connection ptx-ac-4
Name                    State      Time                   Logmsg
===========================================================================================================================================================================================================================================================================================================================================================================
ptx-ac-4                CLOSED     2025-12-03T15:08:48    User request
snc@snc-lab> show devices diff
ptx-ac-4:
      junos-conf-snmp:snmp {
-        location "lab";
+        location "location city";
      }
snc@snc-lab>