Fix invalid JSON at widget initialization

Since `2.6.1` json initializing `magepalGtmDatalayer` is invalid. This breaks scripts execusion, it's IMO critical:
```{
        "*": {
            "magepalGtmDatalayer": {
                "dataLayer": "<?= /* @NoEscape */ $block->getDataLayerName() ?>"
            }
        }
    }```

view/frontend/templates/js.phtml

@@ -49,7 +49,7 @@ $containerCode = $block->getEmbeddedCode();
     {
         "*": {
             "magepalGtmDatalayer": {
-                "dataLayer": "<?= /* @noEscape */ $block->getDataLayerName() ?>",
+                "dataLayer": "<?= /* @noEscape */ $block->getDataLayerName() ?>"
             }
         }
     }