gnome-all: Add deja-dup

We want to promote backing the phone up.
2 jobs for add-deja-dup in 4 minutes and 18 seconds (queued for 2 seconds)
latest
Status Job ID Name Coverage
  Package
passed #256596
librem5
build-debian-package

00:01:14

 
  Test Package
passed #256597
librem5
autopkgtest-debian-package

00:03:04