community/nextcloud-client: add qt5-qtquickcontrols dependency
Without this dependency, the nextcloud GUI fails to start even when requested to run in the foreground.
The log prints the following warning, which disappears after installing the new dependency.
[ warning nextcloud.gui.systray /home/buildozer/aports/community/nextcloud-client/src/desktop-3.6.2/src/gui/systray.cpp:145 ]: "qrc:/qml/src/gui/tray/Window.qml:146 Type UserStatusSelectorPage unavailable\nqrc:/qml/src/gui/UserStatusSelectorPage.qml:39 Type UserStatusSelector unavailable\nqrc:/qml/src/gui/UserStatusSelector.qml:16 module "QtQuick.Dialogs" is not installed\n"