invalid csv export extension

[Ahmed-Elrayes]

Summary of problem or feature request

Hello whenever i try to export to csv, it exports with extension .xlsx (this issue presents only in laravel datatables buttons v9.0)
The issue was fixed after i upgraded laravel datatables buttons to version 9.1

System details

• Operating System: MacOS, Windows, Linux server
• PHP Version: 8.0 ++
• Laravel Version: 9.47.0
• Laravel-DataTables Version: 9.0