cockpit: Use drop-in config component for /etc files

Tests:

- Config files are all symlinks in /etc/
- Web interface is available

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

debian/freedombox.maintscript

@@ -92,6 +92,7 @@ rm_conffile /etc/fail2ban/jail.d/apache-auth-freedombox.conf 23.10~
 rm_conffile /etc/apache2/conf-available/bepasty-freedombox.conf 23.10~
 rm_conffile /etc/uwsgi/apps-available/bepasty-freedombox.ini 23.10~
 rm_conffile /etc/apache2/conf-available/calibre-freedombox.conf 23.10~
+rm_conffile /etc/apache2/conf-available/cockpit-freedombox.conf 23.10~
 rm_conffile /etc/apache2/conf-available/deluge-plinth.conf 23.10~
 rm_conffile /etc/dovecot/conf.d/15-freedombox-mail.conf 23.10~
 rm_conffile /etc/dovecot/conf.d/05-freedombox-passdb.conf 23.10~

plinth/modules/cockpit/__init__.py

@@ -8,6 +8,7 @@ from django.utils.translation import gettext_lazy as _
 
 from plinth import app as app_module
 from plinth import cfg, frontpage, menu
+from plinth.config import DropinConfigs
 from plinth.daemon import Daemon
 from plinth.modules.apache.components import Webserver
 from plinth.modules.backups.components import BackupRestore
@@ -41,7 +42,7 @@ class CockpitApp(app_module.App):
 
     app_id = 'cockpit'
 
-    _version = 2
+    _version = 3
 
     def __init__(self):
         """Create components for the app."""
@@ -72,6 +73,11 @@ class CockpitApp(app_module.App):
         packages = Packages('packages-cockpit', ['cockpit'])
         self.add(packages)
 
+        dropin_configs = DropinConfigs('dropin-configs-cockpit', [
+            '/etc/apache2/conf-available/cockpit-freedombox.conf',
+        ])
+        self.add(dropin_configs)
+
         firewall = Firewall('firewall-cockpit', info.name,
                             ports=['http', 'https'], is_external=True)
         self.add(firewall)