Update GNOME critical update notification needle for new fonts

When there are critical updates available, the message differs.
This is the first time we've had critical updates since the
font change.

Signed-off-by: Adam Williamson <awilliam@redhat.com>

needles/gnome/desktop_update_notification_only-criticalupdates-gnome-20250402.json

@@ -0,0 +1,17 @@
+{
+  "area": [
+    {
+      "ypos": 58,
+      "width": 89,
+      "height": 202,
+      "xpos": 159,
+      "type": "match"
+    }
+  ],
+  "properties": [],
+  "tags": [
+    "desktop_update_notification_only",
+    "desktop_update_notification",
+    "DESKTOP-gnome"
+  ]
+}