Closes: #2253
Tests:
- Build a package with this fix included for bullseye-backports
distribution.
- Install into FreedomBox stable system.
- Start dist-upgrade test.
- At the end of the test, wait for plinth to attempt upgrades, and
then confirm that firewalld was upgraded.
- Confirm that firewalld is running.
- Confirm that /etc/firewalld/firewalld.conf has DefaultZone=external.
Signed-off-by: James Valleroy <jvalleroy@mailbox.org>
Reviewed-by: Sunil Mohan Adapa <sunil@medhas.org>