feat(groups/{u,v,w,x}*): vim syntax support

Add vim modeline instructing the editor to use syntax plugin provided by apparmor.
Continuation of #395 to keep the diff list relatively short.

apparmor.d/groups/virt/cockpit-ssh

@@ -14,4 +14,6 @@ profile cockpit-ssh @{exec_path} {
   @{exec_path} mr,
 
   include if exists <local/cockpit-ssh>
-}
+}
+
+# vim:syntax=apparmor