Add CONF_MODEL to core constants (#68806)

* Add CONF_MODEL to core constants

* Use CONF_MODEL in SamsungTV

Co-authored-by: epenet <epenet@users.noreply.github.com>

tests/components/samsungtv/test_media_player.py

@@ -37,7 +37,6 @@ from homeassistant.components.media_player.const import (
     SUPPORT_TURN_ON,
 )
 from homeassistant.components.samsungtv.const import (
-    CONF_MODEL,
     CONF_ON_ACTION,
     CONF_SSDP_RENDERING_CONTROL_LOCATION,
     DOMAIN as SAMSUNGTV_DOMAIN,
@@ -56,6 +55,7 @@ from homeassistant.const import (
     CONF_IP_ADDRESS,
     CONF_MAC,
     CONF_METHOD,
+    CONF_MODEL,
     CONF_NAME,
     CONF_PORT,
     CONF_TIMEOUT,