clang-tidy: use std::move where applicable (#2605)

Co-authored-by: pajlada <rasmus.karlsson@pajlada.com>

src/widgets/helper/Button.cpp

@@ -38,7 +38,7 @@ Button::Button(BaseWidget *parent)
 
 void Button::setMouseEffectColor(boost::optional<QColor> color)
 {
-    this->mouseEffectColor_ = color;
+    this->mouseEffectColor_ = std::move(color);
 }
 
 void Button::setPixmap(const QPixmap &_pixmap)