QFileSystemModel: fix leak in unittest detected by ASAN
Amends e524724f9d.
Indirect leak of 24 byte(s) in 1 object(s) allocated from:
#0 0x7f73b50fc1d8 in operator new(unsigned long) (/lib64/libasan.so.8+0xfc1d8) (BuildId: 1827a4c72065a9f25ba519b25166029eebbf519f)
#1 0x7f73b4cc18d4 in std::__detail::_MakeUniq<QSignalSpyPrivate>::__single_object std::make_unique<QSignalSpyPrivate, QSignalSpy*>(QSignalSpy*&&) /usr/include/c++/13/bits/unique_ptr.h:1070
#2 0x7f73b4cbf0a4 in QSignalSpy::QSignalSpy(QSignalSpy::ObjectSignal) src/testlib/qsignalspy.cpp:259
#3 0x55c0e313cd7d in QSignalSpy::QSignalSpy<void (QAbstractItemModel::*)(QModelIndex const&, int, int, QAbstractItemModel::QPrivateSignal)>(QtPrivate::FunctionPointer<void (QAbstractItemModel::*)(QModelIndex const&, int, int, QAbstractItemModel::QPrivateSignal)>::Object const*, void (QAbstractItemModel::*)(QModelIndex const&, int, int, QAbstractItemModel::QPrivateSignal)) (build/tests/auto/gui/itemmodels/qfilesystemmodel/tst_qfilesystemmodel+0x83d7d) (BuildId: b2e416794e25fdb925a191cc4a5efe3cb04efb0e)
#4 0x55c0e30eccac in tst_QFileSystemModel::prepareTestModelRoot(QFileSystemModel*, QString const&, QSignalSpy**, QSignalSpy**) tests/auto/gui/itemmodels/qfilesystemmodel/tst_qfilesystemmodel.cpp:392
#5 0x55c0e30edacf in tst_QFileSystemModel::rowCount() tests/auto/gui/itemmodels/qfilesystemmodel/tst_qfilesystemmodel.cpp:420
Pick-to: 6.7 6.5 6.2
Change-Id: Ia085f9235f3bec252290f4fbe5ea0958f91a5e5a
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
(cherry picked from commit 5686af295c98a5ed4b0793ad0098cef76f39a2d7)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
741c1d0f11