Fix mem leak + add signal finished

src/mdn/mdnwarningjob.cpp

@@ -61,6 +61,8 @@ void MDNWarningJob::start()
             }
         }
     }
+    Q_EMIT finished();
+    deleteLater();
 }
 
 const Akonadi::Item &MDNWarningJob::item() const

src/mdn/mdnwarningjob.h

@@ -42,6 +42,9 @@ public:
     Q_REQUIRED_RESULT ResponseMDN response() const;
     void setResponse(ResponseMDN newResponse);
 
+Q_SIGNALS:
+    void finished();
+
 private:
     Q_REQUIRED_RESULT QPair<bool, KMime::MDN::SendingMode> modifyItem();
     Akonadi::Item mItem;