add new expression to provider

Author: JoMessina

src/ExpressionLanguage/Provider.php

@@ -17,6 +17,7 @@ public function getFunctions(): array
             new Base64Decode('base64Decode'),
             new TemporaryFile('temporaryFile'),
             new InSql('inSql'),
+            new Download('downloadFile'),
         ];
     }
 }