Fix new thread loading

If a thread was created by the local user fetchMore() won't find the pending event that created it so make sure it is found and added.

src/models/threadmodel.h

@@ -135,6 +135,7 @@ private:
     std::optional<QString> m_nextBatch = QString();
     bool m_addingPending = false;
 
+    void checkPending();
     void addNewEvent(const Quotient::RoomEvent *event);
     void addModels();
     void clearModels();