Exceptions not documented when opening a file

It would be useful for methods like ExcelReaderFactory.CreateReader to document the possible exceptions that can be thrown.

For example, we had a corrupted .xlsx file that threw a [System.IO.InvalidDataException](https://docs.microsoft.com/en-us/dotnet/api/system.io.invaliddataexception?view=net-6.0), which surprisingly does not derive from IOException.