Fix minor warnings

src/timeline/AvatarFlow.qml

@@ -1,6 +1,8 @@
 // SPDX-FileCopyrightText: 2022 James Graham <james.h.graham@protonmail.com>
 // SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
 
+pragma ComponentBehavior: Bound
+
 import QtQuick
 import QtQuick.Controls as QQC2
 import QtQuick.Layouts