NotHaveColumn assertion for data tables

### Background and motivation

As per the documentation https://fluentassertions.com/data/

Currently there is a HaveColumn assertion for data tables, but there is no NotHaveColumn

### API Proposal

this probably isn't right, but should give an indication:

```C#
public class DataTableAssertions
{
public AndConstraint NotHaveColumn(string columnName, string because = "", params object[] becauseArgs);
}
```

### API Usage

```C#
var table = new DataTable();
table.Should().NotHaveColumn("User")
```

### Alternative Designs

_No response_

### Risks

_No response_

Start at the existing DataTableAssertions HaveColumn assertion and review the data-table documentation linked in the issue. Add the proposed NotHaveColumn API for the shown DataTable usage, then verify that the assertion behaves correctly and follows the existing assertion conventions.

Written by the indexing model from the issue text.