roles/strongswan: Update service name

Fedora has renamed the *strongswan* service to *strongswan-starter*.
The *strongswan* service now controls strongSwan via Vici, which uses a
different configuration format and is not compatible with the files in
`/etc/strongswan/ipsec.d`.  As I am migrating everything to Wireguard
now, it does not make sense to rewrite all of the IPsec configuration in
this new format, so using the legacy format with the renamed service
makes more sense.

roles/dch-vpn-server/tasks/main.yml

@@ -35,5 +35,5 @@
 
 - name: ensure strongswan is running
   service:
-    name=strongswan
+    name=strongswan-starter
     state=started

roles/strongswan/handlers/main.yml

@@ -1,4 +1,4 @@
 - name: restart strongswan
   service:
-    name=strongswan
+    name=strongswan-starter
     state=restarted

roles/strongswan/tasks/main.yml

@@ -30,5 +30,5 @@
 
 - name: ensure strongswan starts at boot
   service:
-    name=strongswan
+    name=strongswan-starter
     enabled=yes