fix: auto import fumble

Author: paoloricciuti

packages/svelte/src/compiler/phases/3-transform/client/transform-template/index.js

@@ -1,7 +1,7 @@
 /**
  * @import { TemplateOperations } from "../types.js"
  */
-import { template_to_string } from './to-string';
+import { template_to_string } from './to-string.js';
 
 /**
  * @param {TemplateOperations} items