Fix Chip.shape
's side is not used when provided in Material 3 (#132941)
fixes [Chip border side color not working in Material3](https://github.com/flutter/flutter/issues/132922)
### Code sample
<details>
<summary>expand to view the code sample</summary>
```dart
import 'package:flutter/material.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({super.key});
@override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData(
useMaterial3: true,
chipTheme: const ChipThemeData(
// shape: RoundedRectangleBorder(
// side: BorderSide(color: Colors.amber),
// borderRadius: BorderRadius.all(Radius.circular(12)),
// ),
// side: BorderSide(color: Colors.red),
),
),
home: const Example(),
);
}
}
class Example extends StatelessWidget {
const Example({super.key});
@override
Widget build(BuildContext context) {
return const Scaffold(
body: Center(
child: RawChip(
shape: RoundedRectangleBorder(
side: BorderSide(color: Colors.amber),
borderRadius: BorderRadius.all(Radius.circular(12)),
),
// side: BorderSide(color: Colors.red),
label: Text('Chip'),
),
),
);
}
}
```
</details>
---
### Before
When `RawChip.shape` is provided with a `BorderSide`.
```dart
body: Center(
child: RawChip(
shape: RoundedRectangleBorder(
side: BorderSide(color: Colors.amber),
borderRadius: BorderRadius.all(Radius.circular(12)),
),
label: Text('Chip'),
),
),
```

When `RawChip.shape` is provided with a `BorderSide` and also `RawChip.side` is provided. The `RawChip.side` overrides the shape's side.
```dart
body: Center(
child: RawChip(
shape: RoundedRectangleBorder(
side: BorderSide(color: Colors.amber),
borderRadius: BorderRadius.all(Radius.circular(12)),
),
side: BorderSide(color: Colors.red),
label: Text('Chip'),
),
),
```

---
### After
When `RawChip.shape` is provided with a `BorderSide`.
```dart
body: Center(
child: RawChip(
shape: RoundedRectangleBorder(
side: BorderSide(color: Colors.amber),
borderRadius: BorderRadius.all(Radius.circular(12)),
),
label: Text('Chip'),
),
),
```

When `RawChip.shape` is provided with a `BorderSide` and also `RawChip.side` is provided. The `RawChip.side` overrides the shape's side.
```dart
body: Center(
child: RawChip(
shape: RoundedRectangleBorder(
side: BorderSide(color: Colors.amber),
borderRadius: BorderRadius.all(Radius.circular(12)),
),
side: BorderSide(color: Colors.red),
label: Text('Chip'),
),
),
```

---