internal/rosa: use type P in helper interface

This is easier to type and serialises correctly.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/dbus.go

@@ -36,7 +36,7 @@ func init() {
 		Description: "a message bus system",
 		Website:     "https://www.freedesktop.org/wiki/Software/dbus/",
 
-		Dependencies: []PArtifact{
+		Dependencies: P{
 			GLib,
 			Libexpat,
 		},