[AssetMapper] Merging outdated and update

Page: https://symfony.com/doc/6.4/frontend/asset_mapper.html#importing-3rd-party-javascript-packages

Reason: No need for 2 code blocks containing almost the same.

Author: ThomasLandauer

frontend/asset_mapper.rst

@@ -228,30 +228,23 @@ command to download the files on other computers if some are missing:
 
     The ``importmap:install`` command was introduced in Symfony 6.4.
 
-You can check for available updates for your third-party packages by running:
+You can update your third-party packages to their current versions by running:
 
 .. code-block:: terminal
 
     # check for updates for all packages
     $ php bin/console importmap:outdated
+    # update them
+    $ php bin/console importmap:update
 
-    # check for updates for the given list of packages
+    # only for the given list of packages
+    $ php bin/console importmap:update bootstrap lodash
     $ php bin/console importmap:outdated bootstrap lodash
 
 .. versionadded:: 6.4
 
     The ``importmap:outdated`` command was introduced in Symfony 6.4.
 
-To update third-party packages in your ``importmap.php`` file, run:
-
-.. code-block:: terminal
-
-    # updates all packages
-    $ php bin/console importmap:update
-
-    # updates only the given list of packages
-    $ php bin/console importmap:update bootstrap lodash
-
 How does the importmap Work?
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~