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)

src/widgets/helper/ChannelView.cpp

@@ -550,7 +550,7 @@ bool ChannelView::getEnableScrollingToBottom() const
 
 void ChannelView::setOverrideFlags(boost::optional<MessageElementFlags> value)
 {
-    this->overrideFlags_ = value;
+    this->overrideFlags_ = std::move(value);
 }
 
 const boost::optional<MessageElementFlags> &ChannelView::getOverrideFlags()
@@ -647,7 +647,7 @@ void ChannelView::setChannel(ChannelPtr underlyingChannel)
     this->channelConnections_.push_back(this->channel_->messageAppended.connect(
         [this](MessagePtr &message,
                boost::optional<MessageFlags> overridingFlags) {
-            this->messageAppended(message, overridingFlags);
+            this->messageAppended(message, std::move(overridingFlags));
         }));
 
     this->channelConnections_.push_back(
@@ -753,7 +753,7 @@ ChannelPtr ChannelView::sourceChannel() const
 
 void ChannelView::setSourceChannel(ChannelPtr sourceChannel)
 {
-    this->sourceChannel_ = sourceChannel;
+    this->sourceChannel_ = std::move(sourceChannel);
 }
 
 bool ChannelView::hasSourceChannel() const

src/widgets/helper/SearchPopup.cpp

@@ -66,7 +66,7 @@ SearchPopup::SearchPopup(QWidget *parent)
 
 void SearchPopup::setChannelFilters(FilterSetPtr filters)
 {
-    this->channelFilters_ = filters;
+    this->channelFilters_ = std::move(filters);
 }
 
 void SearchPopup::setChannel(const ChannelPtr &channel)