Fix GetNotificationsReport

XXClient

• Add NotificationReport array coding helpers.
• Fix GetNotificationsReport` so it returns array.

XXMessengerClient

• Update MessengerGetNotificationReport.
• Rename MessengerGetNotificationReport to MessengerGetNotificationReports.

Sources/XXClient/Models/NotificationReport.swift

@@ -45,3 +45,13 @@ extension NotificationReport: Codable {
     try JSONEncoder().encode(self)
   }
 }
+
+extension Array where Element == NotificationReport {
+  public static func decode(_ data: Data) throws -> Self {
+    try JSONDecoder().decode(Self.self, from: data)
+  }
+
+  public func encode() throws -> Data {
+    try JSONEncoder().encode(self)
+  }
+}