Revert "Qt: set breeze as the default theme"

This reverts commit 4a6d8f422e.

Adding a dependency to `kde-style-breeze` pulls in around 35 new packages,
for an additional size of 40 MB (unpacked). It's basically a part of the
KDE stack that is installed. Not nice for users who don't run KDE.

debian/control

@@ -55,7 +55,6 @@ Package: kali-themes
 Architecture: all
 Depends:
  kali-themes-common (= ${source:Version}),
- kde-style-breeze,
 # gsettings and other config files reference those fonts
  fonts-cantarell,
  fonts-firacode,

debian/kali-themes.postinst

@@ -77,6 +77,9 @@ if [ "$1" = "configure" ]; then
 	if dpkg --compare-versions "$2" lt "2021.1.1"; then
 	    remove_config_file /etc/xdg/Trolltech.conf
 	fi
+	if dpkg --compare-versions "$2" lt "2021.1.2"; then
+	    install_config_file /etc/xdg/qt5ct/qt5ct.conf force
+	fi
 	if dpkg --compare-versions "$2" lt "2021.2.1"; then
 	    install_config_file /etc/xdg/xfce4/whiskermenu/defaults.rc force
 	fi
@@ -97,7 +100,6 @@ if [ "$1" = "configure" ]; then
 	    install_config_file /etc/lightdm/lightdm-gtk-greeter.conf force
 	    install_config_file /etc/xdg/kickoffrc force
 	    install_config_file /etc/xdg/menus/xfce-settings-manager.menu force
-	    install_config_file /etc/xdg/qt5ct/qt5ct.conf force
 	    install_config_file /etc/xdg/xfce4/panel/default.xml force
 	    install_config_file /etc/xdg/xfce4/xfconf/xfce-perchannel-xml/xfce4-session.xml force
 	    install_config_file /etc/xdg/xfce4/xfconf/xfce-perchannel-xml/xfwm4.xml force