Fix clazy invalid slot warning

Author: nyalldawson

python/core/layout/qgslayoutitem.sip.in

@@ -852,6 +852,9 @@ Cancels the current item command and discards it.
 Returns whether the item should be drawn in the current context.
 %End
 
+    virtual QgsExpressionContext createExpressionContext() const;
+
+
   public slots:
 
     virtual void refresh();
@@ -900,9 +903,6 @@ Rotates the item by a specified ``angle`` in degrees clockwise around a specifie
 .. seealso:: :py:func:`itemRotation`
 %End
 
-    virtual QgsExpressionContext createExpressionContext() const;
-
-
   signals:
 
     void frameChanged();

src/core/layout/qgslayoutitem.h

@@ -765,6 +765,8 @@ class CORE_EXPORT QgsLayoutItem : public QgsLayoutObject, public QGraphicsRectIt
      */
     bool shouldDrawItem() const;
 
+    QgsExpressionContext createExpressionContext() const override;
+
   public slots:
 
     /**
@@ -809,8 +811,6 @@ class CORE_EXPORT QgsLayoutItem : public QgsLayoutObject, public QGraphicsRectIt
     */
     virtual void rotateItem( const double angle, const QPointF &transformOrigin );
 
-    QgsExpressionContext createExpressionContext() const override;
-
   signals:
 
     /**