minor #20790 Add doc for option --dry-run for the command importmap:require (chadyred)

This PR was merged into the 7.3 branch.

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Add doc for option `--dry-run` for the command `importmap:require`

Hello,

Docs added ( #20753) make with  `@smnandre`

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2243ab9 doc: Add doc for option `--dry-run` for the command `importmap:require` of the AssetMapper component

Author: javiereguiluz

frontend/asset_mapper.rst

@@ -215,6 +215,11 @@ to add any `npm package`_:
 
     $ php bin/console importmap:require bootstrap
 
+.. tip::
+
+    The command takes the well-know ``--dry-run`` option to simulate the installation of the packages, useful
+    to show what will be installed without altering anything.
+
 This adds the ``bootstrap`` package to your ``importmap.php`` file::
 
     // importmap.php