minor #18401 Update asset_mapper.rst (abdellahrk)

This PR was merged into the 6.3 branch.

Discussion
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Update asset_mapper.rst

update typo at Lazily Importing CSS from a JavaScript File

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Commits
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3ec0fee Update asset_mapper.rst

Author: javiereguiluz

frontend/asset_mapper.rst

@@ -391,7 +391,7 @@ This *can* work with importmaps, but it should *not* be used for critical CSS
 that needs to be loaded before the page is rendered because the browser
 won't download the CSS until the JavaScript file executed.
 
-However, if you *do* want to lazily-load a CSS file, you an make this work
+However, if you *do* want to lazily-load a CSS file, you can make this work
 by using the ``importmap:require`` command and pointing it at a CSS file.
 
 .. code-block:: terminal