Refactor: Remove deprecated methods

- removed deprecated method "loadConfigFile" from "Magento\Framework\App\DeploymentConfig\Reader"

Author: andrewbess

lib/internal/Magento/Framework/App/DeploymentConfig/Reader.php

@@ -124,21 +124,4 @@ public function load($fileKey = null)
         }
         return $result ?: [];
     }
-
-    /**
-     * Loads the configuration file.
-     *
-     * @param string $fileKey The file key
-     * @param string $pathConfig The path config
-     * @param bool $ignoreInitialConfigFiles Whether ignore custom pools
-     * @return array
-     * @throws FileSystemException
-     * @throws RuntimeException
-     * @deprecated 100.2.0 Magento does not support custom config file pools since 2.2.0 version
-     * @SuppressWarnings(PHPMD.UnusedFormalParameter)
-     */
-    public function loadConfigFile($fileKey, $pathConfig, $ignoreInitialConfigFiles = false)
-    {
-        return $this->load($fileKey);
-    }
 }