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

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

internal/engine/experiment/simplequicping/simplequicping.go

@@ -112,12 +112,11 @@ var (
 )
 
 // Run implements ExperimentMeasurer.Run.
-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 {
+	_ = args.Callbacks
+	measurement := args.Measurement
+	sess := args.Session
+
 	if measurement.Input == "" {
 		return errNoInputProvided
 	}

internal/engine/experiment/simplequicping/simplequicping_test.go

@@ -65,7 +65,12 @@ func TestMeasurer_run(t *testing.T) {
 			MockableLogger: model.DiscardLogger,
 		}
 		callbacks := model.NewPrinterCallbacks(model.DiscardLogger)
-		err := m.Run(ctx, sess, meas, callbacks)
+		args := &model.ExperimentArgs{
+			Callbacks:   callbacks,
+			Measurement: meas,
+			Session:     sess,
+		}
+		err := m.Run(ctx, args)
 		return meas, m, err
 	}