scroll to first entry in the preset strip when switching paintop

BUG:327128

krita/ui/widgets/kis_preset_selector_strip.cpp

@@ -50,6 +50,7 @@ KisPresetSelectorStrip::~KisPresetSelectorStrip()
 void KisPresetSelectorStrip::setPresetFilter(const QString& paintOpId)
 {
     smallPresetChooser->setPresetFilter(paintOpId);
+    m_resourceItemView->scrollTo(m_resourceItemView->model()->index(0, 0));
 }
 
 void KisPresetSelectorStrip::on_leftScrollBtn_pressed()