[ticket/17480] Properly catch RuntimeException if no http handler is available

PHPBB-17480

phpBB/phpbb/file_downloader.php

@@ -74,9 +74,16 @@ class file_downloader
 	 *         message is returned
 	 */
 	public function get(string $host, string $directory, string $filename, int $port = 443, int $timeout = 6)
+	{
+		try
 		{
 			// Initialize Guzzle client
 			$client = $this->create_client($host, $port, $timeout);
+		}
+		catch (\RuntimeException $exception)
+		{
+			throw new runtime_exception($exception->getMessage());
+		}
 
 		// Set default values for error variables
 		$this->error_number = 0;