QmlDesigner: Add support for Component type

Component type is added to Component Library and can be dragged to
the scene. Items under the component are not shown in the scene.

Fixes: QDS-5093
Change-Id: I0c80647e73124866a8b772022a761ca6cbb545a1
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>

src/libs/qmljs/qmljscheck.cpp

@@ -617,7 +617,6 @@ class UnsupportedTypesByQmlUi : public QStringList
 {
 public:
     UnsupportedTypesByQmlUi() : QStringList({"ShaderEffect",
-                                             "Component",
                                              "Drawer"})
     {
         append(UnsupportedTypesByVisualDesigner());