Complaints about deprecations throughout sample apps

[pbelbin]

Your Environment

• Plugin version: 4.3.0
• Platform: iOS or Android both
• OS version: macOS 11.2.3
• Device manufacturer / model: doesn't matter
• Flutter info (flutter doctor):

  
  flutter doctor                   
  Doctor summary (to see all details, run flutter doctor -v):
  [✓] Flutter (Channel stable, 2.5.2, on macOS 11.2.3 20D91 darwin-x64, locale en-US)
  [✓] Android toolchain - develop for Android devices (Android SDK version 29.0.3)
  [✓] Xcode - develop for iOS and macOS
  [✓] Chrome - develop for the web
  [✓] Android Studio (version 2020.3)
  [✓] VS Code (version 1.60.2)
  [✓] Connected device (1 available)

• No issues found!

* Plugin config: not relevant, since this is within the source tree.* 

## Expected Behavior
No deprecated code should be in the codebase

## Actual Behavior
Warnings throughout regarding deprecations (at least in the examples)

```dart
@override
  Widget build(BuildContext context) {
    const labelStyle = TextStyle(color: Colors.blue, fontSize: 16.0);

    return new Scaffold(
        appBar: new AppBar(
            brightness: Brightness.light,   <--- complaint that it's deprecated
            leading: IconButton(

Steps to Reproduce

1. Open the code using VSCode with flutter 2.5.2
2. Examine the 'Problems' pane of VSCode, you'll see a lot of complaints about deprecations

Context

I'm trying to build the sample apps.

Debug logs

not needed, this is in the editor, not a runtime problem.

[christocracy]

Is there some particular warning you'd like to show?

[christocracy]

I see your little screenshot now.

The /example UI code hasn't been looked at in a while.

Those warnings are not related to the plugin api itself.

The /example code will be updated soon.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions. You may also mark this issue as a "discussion" and I will leave this open.

[pbelbin]

Has the 'will be updated soon' happened?

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions. You may also mark this issue as a "discussion" and I will leave this open.

[pbelbin]

It's been a while since this issue was opened. Has the concern been addressed?

[pbelbin]

Flutter has moved on to 3.3, are there other updates that should be expected too, as a result?

[github-actions[bot]]

This issue is stale because it has been open for 30 days with no activity.

[github-actions[bot]]

This issue was closed because it has been inactive for 14 days since being marked as stale.