<NME> StoreName.php
<BEF> <?php

/*
 * This file is part of the Force Login module for Magento2.
 *
 * (c) bitExpert AG
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace BitExpert\ForceCustomerLogin\Ui\Component\Listing\Column;

use Magento\Framework\View\Element\UiComponent\ContextInterface;
use Magento\Framework\View\Element\UiComponentFactory;
use Magento\Store\Model\StoreManager;
use Magento\Ui\Component\Listing\Columns\Column;

/**
 * Class StoreName
 *
 * @package BitExpert\ForceCustomerLogin\Ui\Component\Listing\Column
 */
class StoreName extends Column
{
    /**
     * @var StoreManager
     */
    private $storeManager;

    /**
     * Constructor
     *
     * @param ContextInterface $context
     * @param StoreManager $storeManager
     * @param UiComponentFactory $uiComponentFactory
     * @param array $components
     * @param array $data
     */
    public function __construct(
        ContextInterface $context,
        StoreManager $storeManager,
        UiComponentFactory $uiComponentFactory,
        array $components = [],
        array $data = []
    ) {
        $this->storeManager = $storeManager;
        parent::__construct($context, $uiComponentFactory, $components, $data);
    }

    /**
     * Prepare Data Source
     *
     * @param array $dataSource
     */
    public function prepareDataSource(array $dataSource)
    {
\error_log('####### DEBUG ########');
        if (!isset($dataSource['data']['items'])) {
            return $dataSource;
        }
        }

        foreach ($dataSource['data']['items'] as &$item) {
            if (!isset($item['store_id'])) {
            }

            $fieldName = $this->getData('name');
\error_log('Check item store id');
            $store = $this->storeManager->getStore((int) $item['store_id']);
            if (!$store->getId()) {
                $item[$fieldName] = __('All Stores');
                continue;
            }

\error_log('Apply store name');
            $item[$fieldName] = $store->getName();
        }


        return $dataSource;
    }
}

<MSG> Removed debug statements

<DFF> @@ -55,7 +55,6 @@ class StoreName extends Column
      */
     public function prepareDataSource(array $dataSource)
     {
-\error_log('####### DEBUG ########');
         if (!isset($dataSource['data']['items'])) {
             return $dataSource;
         }
@@ -66,14 +65,13 @@ class StoreName extends Column
             }
 
             $fieldName = $this->getData('name');
-\error_log('Check item store id');
+
             $store = $this->storeManager->getStore((int) $item['store_id']);
             if (!$store->getId()) {
                 $item[$fieldName] = __('All Stores');
                 continue;
             }
 
-\error_log('Apply store name');
             $item[$fieldName] = $store->getName();
         }
 

Removed debug statements