[LyX/master] Pass SocketCallback object as const reference

[Jean-Marc Lasgouttes]

commit 980f91d12ee9f47ad944ec0f0befb9c638511bdc
Author: Jean-Marc Lasgouttes <lasgouttes at lyx.org>
Date:   Sat Sep 14 20:19:34 2024 +0200

    Pass SocketCallback object as const reference
    
    Spotted by Coverity scan.
---
 src/frontends/qt/GuiApplication.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/frontends/qt/GuiApplication.cpp b/src/frontends/qt/GuiApplication.cpp
index 1c9edc0c9c..fb974f7e1d 100644
--- a/src/frontends/qt/GuiApplication.cpp
+++ b/src/frontends/qt/GuiApplication.cpp
@@ -744,7 +744,7 @@ class SocketNotifier : public QSocketNotifier
 {
 public:
 	/// connect a connection notification from the LyXServerSocket
-	SocketNotifier(QObject * parent, int fd, Application::SocketCallback func)
+	SocketNotifier(QObject * parent, int fd, Application::SocketCallback const & func)
 		: QSocketNotifier(fd, QSocketNotifier::Read, parent), func_(func)
 	{}