Queried Nullable values should be able to batch-insert similarly

[mdonkers]

Issue description

When reading, a 'record' is initialized based on reflection, as is shown also in examples:

	record := make([]any, len(columnTypes), len(columnTypes)+recordExtraSpace)
	// Have to initialize 'empty' values to write actual values to
	for i := range columnTypes {
		record[i] = reflect.New(columnTypes[i].ScanType()).Interface()
	}

	rows.Scan(record...)

This will initialize Nullable columns such as Nullable(String) as double pointer **String type.

However when inserting this value in exactly the same format, this fails:

batch, err := c.conn.PrepareBatch(c.ctx, query)

batch.Append(record...)

Which will throw an error indicating **String cannot be inserted as Nullable(String)

Configuration

OS: Linux

Interface: Native

Driver version: 2.3.0

Go version: 1.19

ClickHouse Server version: 22.9+