sdk: Install some flatpak-builder recommended dependencies

Both elfutils and fuse are "recommended" flatpak-builder dependencies
(the latter indirectly via flatpak-builder -> requires flatpak ->
recommends xdg-desktop-portal -> requires fuse), but they're needed for
some expected core functionality to work. In particular, flatpak-builder
needs fuse unless run with `--disable-rofiles-fuse`, and elfutils is
required for debug info to be stripped.

https://phabricator.apertis.org/T8751



Signed-off-by: Ryan Gonzalez <ryan.gonzalez@collabora.com>

ospack-basesdk.yaml

@@ -287,12 +287,16 @@ actions:
       - dh-exec
       - docker.io
       - dosfstools
+      # needed for flatpak-builder
+      - elfutils
       - evince
       - fakeroot
       - file
       - firefox-esr
       - flatpak-builder
       - flex
+      # needed for flatpak-builder
+      - fuse
       - g++-aarch64-linux-gnu
       - g++-arm-linux-gnueabihf
       - gawk