[education/rkward] rkward/autotests: Add missing include

[Thomas Friedrichsmeier]

Git commit 02e95931485e610ed8e41e5dbf791a3b8fab8210 by Thomas Friedrichsmeier.
Committed on 13/10/2025 at 15:56.
Pushed by tfry into branch 'master'.

Add missing include

M  +1    -0    rkward/autotests/core_test.cpp

https://invent.kde.org/education/rkward/-/commit/02e95931485e610ed8e41e5dbf791a3b8fab8210

diff --git a/rkward/autotests/core_test.cpp b/rkward/autotests/core_test.cpp
index 1345dfd81..76e4091d8 100644
--- a/rkward/autotests/core_test.cpp
+++ b/rkward/autotests/core_test.cpp
@@ -9,6 +9,7 @@ SPDX-License-Identifier: GPL-2.0-or-later
 #include <QApplication>
 #include <QButtonGroup>
 #include <QDir>
+#include <QElapsedTimer>
 #include <QFile>
 #include <QLoggingCategory>
 #include <QObject>