Fix: missing EmbedLiveSample macro (#37366)

This commit will add the `EmbedLiveSample` macro to the page and fix issue #37366

files/en-us/learn_web_development/extensions/forms/form_validation/index.md

@@ -534,7 +534,7 @@ email.addEventListener("input", (event) => {
 });
 ```
 
-You can try this example in the page at the {{LiveSampleLink('Extending_built-in_form_validation', 'Live sample demo link')}}.
+You can try this example in the page at the {{EmbedLiveSample("extending_built-in_form_validation", "100%", 150)}}.
 Try submitting an invalid email address, a valid email address that doesn't end in `@example.com`, and one that does end in `@example.com`.
 
 #### A more detailed example