Taha Tesser 40dda2b4bb
Add DataColumn.headingRowAlignment for DataTable (#144006)
fixes [[`DataTable`]  Unable to center the label of a DataColumn without side effects](https://github.com/flutter/flutter/issues/143340)

### 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(
      debugShowCheckedModeBanner: false,
      home: MaterialApp(
        home: Material(
          child: DataTable(
            columns: <DataColumn>[
              DataColumn(
                headingRowAlignment: MainAxisAlignment.center,
                onSort: (int columnIndex, bool ascending) {},
                label: const Text('Header'),
              ),
            ],
            sortColumnIndex: 0,
            rows: const <DataRow>[
              DataRow(
                cells: <DataCell>[
                  DataCell(Center(child: Text('Data'))),
                ],
              ),
            ],
          ),
        ),
      ),
    );
  }
}
```

</details>

### Center `DataColumn.mainAxisAlignment` without sort arrow
![Screenshot 2024-03-25 at 17 13 05](https://github.com/flutter/flutter/assets/48603081/0c91d279-23e8-40d9-ab86-c08013c73666)

### Center `DataColumn.mainAxisAlignment` with sort arrow

![Screenshot 2024-03-25 at 17 11 54](https://github.com/flutter/flutter/assets/48603081/d042d02a-e7be-4f47-a90c-8a1ee0f7f5f3)
2024-04-01 09:42:51 +00:00
..
2024-03-19 17:58:13 +00:00