Fix: Show update notifications

If the app was build via `qmake`, no update notifications where shown
even if the `with_update_service` configuration option was set.
12 jobs for 194-get-rid-of-the-default-inbox in 12 minutes and 50 seconds (queued for 1 second)
Status Job ID Name Coverage
  Images
manual #57689123
allowed to fail manual
build_image_android
manual #57689118
allowed to fail manual
build_image_ubuntu
manual #57689120
allowed to fail manual
build_image_win32
manual #57689122
allowed to fail manual
build_image_win64
 
  Build
passed #57689130
android_armv7

00:10:05

passed #57689131
android_x86

00:10:40

manual #57689129
macos allowed to fail manual
macos
passed #57689124
ubuntu_appimage

00:12:49

passed #57689125
win32_build

00:05:42

manual #57689127
windows allowed to fail manual
win32_vs_build
passed #57689126
win64_build

00:05:38

manual #57689128
windows allowed to fail manual
win64_vs_build