minor #19453 [AssetMapper] Deleting duplicated sentence (ThomasLandauer)

This PR was squashed before being merged into the 6.4 branch.

Discussion
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[AssetMapper] Deleting duplicated sentence

Page: https://symfony.com/doc/6.4/frontend/asset_mapper.html#handling-css

Besides "nothing additional happens" didn't make sense to me.

Commits
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035a424 [AssetMapper] Deleting duplicated sentence

Author: javiereguiluz

frontend/asset_mapper.rst

@@ -420,10 +420,8 @@ the page as ``link`` tags in the order they were imported.
 .. note::
 
     Importing a CSS file is *not* something that is natively supported by
-    JavaScript modules and normally causes an error. AssetMapper makes this
-    work by adding an importmap entry for each CSS file that is valid, but
-    does nothing. AssetMapper adds a ``link`` tag for each CSS file, but when
-    the JavaScript executes the ``import`` statement, nothing additional happens.
+    JavaScript modules. AssetMapper makes this work by adding an importmap entry for each CSS file,
+    and then adds a ``link`` tag for each CSS file.
 
 .. _asset-mapper-3rd-party-css: