Fix #8603: Don't give focus to text filter when opening Object GUI (#9547)

(cherry picked from commit 66620b497b)

src/object_gui.cpp

@@ -117,7 +117,6 @@ public:
 		NWidgetMatrix *matrix = this->GetWidget<NWidgetMatrix>(WID_BO_SELECT_MATRIX);
 		matrix->SetScrollbar(this->GetScrollbar(WID_BO_SELECT_SCROLL));
 
-		this->SetFocusedWidget(WID_BO_FILTER);
 		this->GetWidget<NWidgetMatrix>(WID_BO_OBJECT_MATRIX)->SetCount(4);
 
 		ResetObjectToPlace();