Repository: flutter
Issue: The TableBorder's borderRadius param is not applied when `isUniform` condition is not true.
Labels: framework,has reproducible steps,P3,team-framework,triaged-framework,found in release: 3.19,found in release: 3.20

### Steps to reproduce

1. Run `flutter create --sample=material.DataTable.1 mysample`.
2. Provide any border param which makes `isUniform`(at table_border.dart:91) expression not true(like this) for the DataTable:
```dart
      border: TableBorder(
          left: const BorderSide(color: Color(0xFFE5EBF1)),
          top: const BorderSide(color: Color(0xFFE5EBF1)),
          right: const BorderSide(color: Color(0xFFE5EBF1)),
          bottom: const BorderSide(color: Color(0xFFE5EBF1)),
          horizontalInside: const BorderSide(color: Color(0xFFE5EBF1)),
          borderRadius: BorderRadius.circular(8)),
```
3. Run `flutter run` and watch how the DataTable border paints.


### Expected results

<img width="912" alt="截屏2024-03-04 18 14 19" src="https://github.com/flutter/flutter/assets/25654559/866a6bed-f523-4d1c-b836-5e41606b4911">


### Actual results

<img width="912" alt="截屏2024-03-04 18 14 40" src="https://github.com/flutter/flutter/assets/25654559/c67ec3b8-bf56-4c9b-a91e-60ac9517b940">

### Code sample

<details open><summary>Code sample</summary>

```dart
import 'package:flutter/material.dart';

/// Flutter code sample for [DataTable].

void main() => runApp(const DataTableExampleApp());

class DataTableExampleApp extends StatelessWidget {
  const DataTableExampleApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: const Text('DataTable Sample')),
        body: const DataTableExample(),
      ),
    );
  }
}

class DataTableExample extends StatelessWidget {
  const DataTableExample({super.key});

  @override
  Widget build(BuildContext context) {
    return DataTable(
      border: TableBorder(
          left: const BorderSide(color: Color(0xFFE5EBF1)),
          top: const BorderSide(color: Color(0xFFE5EBF1)),
          right: const BorderSide(color: Color(0xFFE5EBF1)),
          bottom: const BorderSide(color: Color(0xFFE5EBF1)),
          horizontalInside: const BorderSide(color: Color(0xFFE5EBF1)),
          borderRadius: BorderRadius.circular(8)),
      columns: const <DataColumn>[
        DataColumn(
          label: Expanded(
            child: Text(
              'Name',
              style: TextStyle(fontStyle: FontStyle.italic),
            ),
          ),
        ),
        DataColumn(
          label: Expanded(
            child: Text(
              'Age',
              style: TextStyle(fontStyle: FontStyle.italic),
            ),
          ),
        ),
        DataColumn(
          label: Expanded(
            child: Text(
              'Role',
              style: TextStyle(fontStyle: FontStyle.italic),
            ),
          ),
        ),
      ],
      rows: const <DataRow>[
        DataRow(
          cells: <DataCell>[
            DataCell(Text('Sarah')),
            DataCell(Text('19')),
            DataCell(Text('Student')),
          ],
        ),
        DataRow(
          cells: <DataCell>[
            DataCell(Text('Janine')),
            DataCell(Text('43')),
            DataCell(Text('Professor')),
          ],
        ),
        DataRow(
          cells: <DataCell>[
            DataCell(Text('William')),
            DataCell(Text('27')),
            DataCell(Text('Associate Professor')),
          ],
        ),
      ],
    );
  }
}

```

</details>


### Screenshots or Video

<details open>
<summary>Screenshots / Video demonstration</summary>

<img width="912" alt="截屏2024-03-04 18 05 10" src="https://github.com/flutter/flutter/assets/25654559/1c906558-7894-4c57-a995-743dfa37946d">

</details>


### Logs

<details open><summary>Logs</summary>

[logs.txt](https://github.com/flutter/flutter/files/14480032/logs.txt)

</details>


### Flutter Doctor output

<details open><summary>Doctor output</summary>

```console
Last login: Mon Mar  4 18:15:30 on ttys010
ra1n@RA1NO3O-MBP ~ % flutter doctor -v 
[✓] Flutter (Channel stable, 3.19.1, on macOS 14.3.1 23D60 darwin-arm64, locale
    zh-Hans-CN)
    • Flutter version 3.19.1 on channel stable at
      /opt/homebrew/Caskroom/flutter/3.19.1/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision abb292a07e (13 days ago), 2024-02-20 14:35:05 -0800
    • Engine revision 04817c99c9
    • Dart version 3.3.0
    • DevTools version 2.31.1
    • Pub download mirror https://pub.flutter-io.cn
    • Flutter download mirror https://storage.flutter-io.cn

[✓] Android toolchain - develop for Android devices (Android SDK version 34.0.0)
    • Android SDK at /Users/ra1n/Library/Android/sdk
    • Platform android-34, build-tools 34.0.0
    • ANDROID_HOME = /Users/ra1n/Library/Android/sdk
    • Java binary at: /Applications/Android
      Studio.app/Contents/jbr/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build
      17.0.9+0-17.0.9b1087.7-11185874)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 15.2)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 15C500b
    • CocoaPods version 1.15.2

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 2023.2)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build
      17.0.9+0-17.0.9b1087.7-11185874)

[✓] Connected device (3 available)
    • RA1NO3O’s iPhone (mobile) • 00008130-00092D8421D0001C • ios            •
      iOS 17.3.1 21D61
    • macOS (desktop)           • macos                     • darwin-arm64   •
      macOS 14.3.1 23D60 darwin-arm64
    • Chrome (web)              • chrome                    • web-javascript •
      Google Chrome 122.0.6261.94

[✓] Network resources
    • All expected network resources are available.

• No issues found!
ra1n@RA1NO3O-MBP ~ % 

```

</details>