minor #1280 Fix loadingContent block name in example (boedah)

This PR was merged into the 2.x branch.

Discussion
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Fix loadingContent block name in example

Just a documentation typo fix.

Commits
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05cbb96 Fix loadingContent block name in example

Author: weaverryan

src/LiveComponent/doc/index.rst

@@ -2254,7 +2254,7 @@ Or override the ``loadingContent`` block:
 .. code-block:: twig
 
     {% component SomeHeavyComponent with { defer: true }) }}
-        {% block content %}Loading...{% endblock %}
+        {% block loadingContent %}Loading...{% endblock %}
     {{ end_component() }}
 
 To change the initial tag from a ``div`` to something else, use the ``loading-tag`` option: