<?php
use Microsoft\Graph\Beta\GraphServiceClient;
use Microsoft\Graph\Beta\Generated\IdentityGovernance\LifecycleWorkflows\Workflows\Item\WorkflowItemRequestBuilderGetRequestConfiguration;
$graphServiceClient = new GraphServiceClient($tokenRequestContext, $scopes);
$requestConfiguration = new WorkflowItemRequestBuilderGetRequestConfiguration();
$queryParameters = WorkflowItemRequestBuilderGetRequestConfiguration::createQueryParameters();
$queryParameters->expand = ["previewScope"];
$requestConfiguration->queryParameters = $queryParameters;
$result = $graphServiceClient->identityGovernance()->lifecycleWorkflows()->workflows()->byWorkflowId('workflow-id')->get($requestConfiguration)->wait();