UI: Fix QStyle memory leak

UI/window-basic-main.cpp

@@ -277,7 +277,9 @@ OBSBasic::OBSBasic(QWidget *parent)
 
 	ui->setupUi(this);
 	ui->previewDisabledWidget->setVisible(false);
-	ui->contextContainer->setStyle(new OBSContextBarProxyStyle);
+	QStyle *contextBarStyle = new OBSContextBarProxyStyle();
+	contextBarStyle->setParent(ui->contextContainer);
+	ui->contextContainer->setStyle(contextBarStyle);
 	ui->broadcastButton->setVisible(false);
 
 	startingDockLayout = saveState();