minor #1568 [Doc] Minor fix in a Live Component code example (javiereguiluz)

This PR was merged into the 2.x branch.

Discussion
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[Doc] Minor fix in a Live Component code example

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| Issues        | -
| License       | MIT

Commits
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c59e52e [Doc] Minro fix in a Live Component code example

Author: weaverryan

src/LiveComponent/doc/index.rst

@@ -833,7 +833,7 @@ of the change:
 
 .. code-block:: javascript
 
-    const rootElement = document.getElementById('favorite-food');
+    const input = document.getElementById('favorite-food');
     input.value = 'sushi';
 
     input.dispatchEvent(new Event('change', { bubbles: true }));
@@ -1007,7 +1007,7 @@ Live components require a single "default action" that is used to
 re-render it. By default, this is an empty ``__invoke()`` method and can
 be added with the ``DefaultActionTrait``. Live components are actually
 Symfony controllers so you can add the normal controller
-attributes/annotations (ie ``#[Cache]``/``#[Security]``) to either the
+attributes/annotations (i.e. ``#[Cache]``/``#[Security]``) to either the
 entire class just a single action.
 
 You can also trigger custom actions on your component. Let's pretend we