refactor: pass experiment arguments using a struct (#983)

Closes https://github.com/ooni/probe/issues/2358.

internal/engine/experiment/torsf/torsf.go

@@ -124,10 +124,10 @@ const maxRuntime = 600 * time.Second
 // set the relevant OONI error inside of the measurement and
 // return nil. This is important because the caller may not submit
 // the measurement if this method returns an error.
-func (m *Measurer) Run(
-	ctx context.Context, sess model.ExperimentSession,
-	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
-) error {
+func (m *Measurer) Run(ctx context.Context, args *model.ExperimentArgs) error {
+	callbacks := args.Callbacks
+	measurement := args.Measurement
+	sess := args.Session
 	ptl, sfdialer, err := m.setup(ctx, sess.Logger())
 	if err != nil {
 		// we cannot setup the experiment