minor #12334 Minor improvement for the docs about the translation:update command (javiereguiluz)

This PR was merged into the 4.3 branch.

Discussion
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Minor improvement for the docs about the translation:update command

After merging #12136, I realized we don't explain this command well ... so let's tweak it.

Commits
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182d927 Minor improvement for the docs about the translation:update command

Author: javiereguiluz

translation.rst

@@ -247,8 +247,14 @@ with these tasks:
 
 .. code-block:: terminal
 
-    # updates the French translation file with the missing strings for that locale
-    $ php bin/console translation:update --dump-messages --force fr
+    # shows all the messages that should be translated for the French language
+    $ php bin/console translation:update --dump-messages fr
+
+    # updates the French translation files with the missing strings for that locale
+    $ php bin/console translation:update --force fr
+
+    # check out the command help to see its options (prefix, output format, domain, etc.)
+    $ php bin/console translation:update --help
 
 The ``translation:update`` command looks for missing translations in:
 
@@ -263,11 +269,6 @@ The ``translation:update`` command looks for missing translations in:
     The extraction of missing translation strings from PHP files was introduced
     in Symfony 4.3.
 
-.. note::
-
-    If you want to see the missing translation strings without actually updating
-    the translation files, remove the ``--force`` option from the command above.
-
 .. _translation-resource-locations:
 
 Translation Resource/File Names and Locations