When slide direction is down, list view inside panel does not scroll

[zakton5]

Describe the bug See title.

To Reproduce Use the code below. Set slideDirection to SlideDirection.DOWN. User panelBuilder to create a list.

Expected behavior I expect to be able to scroll my list down in the panel

Screenshots If applicable, add screenshots to help explain your problem.

Additional context Add any other context about the problem here.

Sample main.dart

import 'package:flutter/material.dart';
import 'package:sliding_up_panel/sliding_up_panel.dart';

void main() async {
  runApp(MyApp());
}

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'SlidingPanelListBug',
      home: SlidingPanelListBug(),
    );
  }
}

class SlidingPanelListBug extends StatefulWidget {
  SlidingPanelListBug({Key key}) : super(key: key);

  @override
  _SlidingPanelListBugState createState() => _SlidingPanelListBugState();
}

class _SlidingPanelListBugState extends State<SlidingPanelListBug> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('List Panel Bug')),
      body: SlidingUpPanel(
        minHeight: 100,
        maxHeight: 300,
        margin: const EdgeInsets.symmetric(horizontal: 16),
        slideDirection: SlideDirection.DOWN,
        color: Colors.white,
        parallaxEnabled: true,
        collapsed: Container(color: Colors.blue),
        panelBuilder: (ScrollController sc) {
          return ListView.builder(
            controller: sc,
            itemCount: 50,
            itemBuilder: (BuildContext context, int i) {
              return Container(
                color: Colors.red,
                padding: const EdgeInsets.all(12.0),
                child: Text("$i"),
              );
            },
          );
        },
        borderRadius: const BorderRadius.only(
          bottomLeft: Radius.circular(16.0),
          bottomRight: Radius.circular(16.0),
        ),
      ),
    );
  }
}