Add json for "update_widgets" push command (#2847)

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Ref PR: home-assistant/mobile-apps-fcm-push#145

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Documentation: home-assistant/companion.home-assistant#

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Sources/PushServer/Tests/SharedPushTests/notification_test_cases.bundle/command_update_widgets.json

@@ -0,0 +1,23 @@
+{
+    "input": {
+        "title": "extra excluded title",
+        "message": "update_widgets",
+        "registration_info": {
+            "app_id": "io.robbie.HomeAssistant.dev",
+            "os_version": "10.15",
+            "app_version": "2024.7"
+        }
+    },
+    "rate_limit": false,
+    "headers": {
+        "apns-push-type": "background"
+    },
+    "payload": {
+        "aps": {
+            "contentAvailable": true
+        },
+        "homeassistant": {
+            "command": "update_widgets"
+        }
+    }
+}