<?php
use Microsoft\Graph\Beta\GraphServiceClient;
use Microsoft\Graph\Beta\Generated\Chats\Item\InstalledApps\InstalledAppsRequestBuilderGetRequestConfiguration;
$graphServiceClient = new GraphServiceClient($tokenRequestContext, $scopes);
$requestConfiguration = new InstalledAppsRequestBuilderGetRequestConfiguration();
$queryParameters = InstalledAppsRequestBuilderGetRequestConfiguration::createQueryParameters();
$queryParameters->expand = ["teamsAppDefinition(\$expand=bot)"];
$requestConfiguration->queryParameters = $queryParameters;
$result = $graphServiceClient->chats()->byChatId('chat-id')->installedApps()->get($requestConfiguration)->wait();