bug #19312 [AssetMapper] Fix importmap code example with multiple entrypoints (smnandre)

This PR was merged into the 6.4 branch.

Discussion
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[AssetMapper] Fix importmap code example with multiple entrypoints

Fix #19311

importmap twig extension method does indeed require an array or a string, and not a variadic : https://github.com/symfony/symfony/blob/6.4/src/Symfony/Bridge/Twig/Extension/ImportMapRuntime.php

Commits
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ebca2e9 Update asset_mapper.rst

Author: OskarStark

frontend/asset_mapper.rst

@@ -1042,7 +1042,7 @@ both ``app`` and ``checkout``:
     {% block importmap %}
         {# do NOT call parent() #}
 
-        {{ importmap('app', 'checkout') }}
+        {{ importmap(['app', 'checkout']) }}
     {% endblock %}
 
 By passing both ``app`` and ``checkout``, the ``importmap()`` function will