zoph: Don't use mod-php instead continue to use php-fpm

Zoph package depends on libapache2-mod-php. This installed and enables mod-php.
Also the process model for apache is switched to prefork. In FreedomBox, we want
mod-event and php-fpm. So, immediately after installing the package, re-run
apache setup to ensure that PHP related changes are undone.

Tests:

- On Bookworm and Trixie, install zoph. Ensure that 'a2query -m php-8.{2,4}'
show that mod-php is disabled. Also 'a2query -m mpm_event' shows it is enabled
and prefork is disabled. Apache is restarted during installation.

- On Bookworm install without patch and notice that mod-php is installed. Apply
patches and notice that mod-php and mpm_prefork are disabled while mpm_event is
enabled.

Signed-off-by: Sunil Mohan Adapa <sunil@medhas.org>
Reviewed-by: James Valleroy <jvalleroy@mailbox.org>

plinth/modules/zoph/__init__.py

@@ -9,6 +9,7 @@ from plinth import app as app_module
 from plinth import cfg, frontpage, menu
 from plinth.config import DropinConfigs
 from plinth.daemon import SharedDaemon
+from plinth.modules.apache import privileged as apache_privileged
 from plinth.modules.apache.components import Webserver
 from plinth.modules.backups.components import BackupRestore
 from plinth.modules.firewall.components import Firewall
@@ -104,6 +105,12 @@ class ZophApp(app_module.App):
             # upgrade of zoph database.
             super().setup(old_version)
 
+        # Zoph brings mod-php as dependency and enables it. Re-run apache setup
+        # to correct it. Disable mod-php, switch back to mpm-event, restart
+        # apache2 if needed. Set old_version to an non-zero value so that
+        # Snakeoil certificate is not regnerated.
+        apache_privileged.setup(old_version=1)
+
         privileged.setup()
         if not old_version:
             self.enable()