fails in autopkgtest on gnome-desktop-testing

[Dan Bungert]

flatpak fails autopkgtest like so:

1125s Updating appstream branch
1125s Updating summary
1125s ok app with mismatched metadata (in summary) can't be installed
1125s ================ test-metadata-validation.sh:158 - app with mismatched metadata (in summary) can't be installed ================
1125s OK closing connection
1125s fusermount: entry for /tmp/test-flatpak-MPRPRX/runtime/doc not found in /etc/mtab
1125s PASS: Flatpak/test-metadata-validation.sh.test
1125s SUMMARY: total=45; passed=38; skipped=0; failed=7; user=205.6s; system=150.8s; maxrss=423860
1125s FAIL: <email address hidden> (Child process exited with code 1)
1125s FAIL: Flatpak/testlibrary.test (Child process killed by signal 6)
1125s FAIL: <email address hidden> (Child process exited with code 1)
1125s FAIL: Flatpak/test-run@system-norevokefs,deltas.wrap.test (Child process exited with code 1)
1125s FAIL: Flatpak/test-run@system,deltas.wrap.test (Child process exited with code 1)
1125s FAIL: Flatpak/test-run@system,nodeltas.wrap.test (Child process exited with code 1)
1125s FAIL: Flatpak/test-run@system-norevokefs,nodeltas.wrap.test (Child process exited with code 1)
1125s /tmp/autopkgtest.Kstx4F/wrapper.sh: Killing leaked background processes: 9343
1125s PID TTY STAT TIME COMMAND
1125s 9343 ? S 0:00 /usr/bin/python3 /usr/libexec/installed-tests/Flatpak/web-server.py repos
1125s autopkgtest [07:37:45]: test gnome-desktop-testing: -----------------------]
1126s autopkgtest [07:37:46]: test gnome-desktop-testing: - - - - - - - - - - results - - - - - - - - - -
1126s gnome-desktop-testing FAIL non-zero exit status 2

https://autopkgtest.ubuntu.com/results/autopkgtest-noble/noble/amd64/f/flatpak/20240324_073939_33ef3@/log.gz