Try to use an older linuxdeployqt appimage

I think the most recent build broke deployments?

.ci/linux/deploy.sh

@@ -25,8 +25,8 @@ for iconSize in 16 32 48 64 128 256 512; do
 done
 
 # Only download the file when not already present
-if ! [ -f linuxdeployqt-continuous-x86_64.AppImage ] ; then
-	wget -c "https://github.com/probonopd/linuxdeployqt/releases/download/continuous/linuxdeployqt-continuous-x86_64.AppImage"
+if ! [ -f linuxdeployqt-6-x86_64.AppImage ] ; then
+	wget -c "https://github.com/probonopd/linuxdeployqt/releases/download/6/linuxdeployqt-6-x86_64.AppImage"
 fi
 chmod a+x linuxdeployqt*.AppImage