internal/rosa: resolve runtime for overlay extras

This is generally for system image creation, so this behaviour makes more sense.

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

internal/rosa/state.go

@@ -1008,9 +1008,9 @@ func (ctx *evalContext) pf(
 		if o.P, err = check.NewAbs(overlay); err != nil {
 			o.P = AbsUsrSrc.Append("extra", overlay)
 		}
-		o.A = make([]pkg.Artifact, len(extraH))
-		for i, h := range extraH {
-			_, a := ctx.t.MustLoad(h)
+		extraA := ctx.t.Append(nil, extraH...)
+		o.A = make([]pkg.Artifact, len(extraA))
+		for i, a := range extraA {
 			o.A[i] = a
 		}
 		attr.Paths = append(attr.Paths, o)