fix build

Signed-off-by: Trial97 <alexandru.tripon97@gmail.com>

launcher/modplatform/ModIndex.h

@@ -25,7 +25,6 @@
 #include <QVariant>
 #include <QVector>
 #include <memory>
-#include <optional>
 
 class QIODevice;
 
@@ -44,7 +43,7 @@ namespace ProviderCapabilities {
 const char* name(ResourceProvider);
 QString readableName(ResourceProvider);
 QStringList hashType(ResourceProvider);
-};  // namespace ProviderCapabilities
+}  // namespace ProviderCapabilities
 
 struct ModpackAuthor {
     QString name;