main: Use the app ID as the program name
I didn't try it on a Librem 5, but this should fix #534 (closed), see https://honk.sigxcpu.org/con/GTK__and_the_application_id.html.
I didn't try it on a Librem 5, but this should fix #534 (closed), see https://honk.sigxcpu.org/con/GTK__and_the_application_id.html.