Cannot request events delta without startDateTime

Describe the bug

Event delta documentation says param startDateTime is optional when working with calendars but class DeltaRequestBuilder always include it in template url causing call to fail with ODataError.

Expected behavior

When performing a normal call without any optional param to get a full delta, no error should append.

How to reproduce

$client->me()
->calendars()
->byCalendarId($remoteId)
->events()
->delta()
->get(
    new DeltaRequestBuilderGetRequestConfiguration([
        'Prefer' => sprintf('outlook.timezone="%s"', $local->getTimeZone()->getName())
    ])
)
->wait()

SDK Version

2.8.0

Latest version known to work for scenario above?

No response

Known Workarounds

No response

Debug output

{
    "error": {
        "code": "ErrorInvalidParameter",
        "message": "The value '' of parameter 'StartDateTime' is invalid."
    }
}

Configuration

No response

Other information

No response

Comienza con src/Generated/Users/Item/Calendars/Item/Events/Delta/DeltaRequestBuilder.php y compara su URL de plantilla con la documentación de Event delta enlazada en el issue. Reproduce la solicitud de delta del calendario sin startDateTime; estará hecho cuando la solicitud tenga éxito sin un error de StartDateTime no válido, mientras que las solicitudes que proporcionen el parámetro sigan funcionando.