minor #10627 Minor tweak for translation:update command (javiereguiluz)

This PR was squashed before being merged into the 4.2 branch (closes #10627).

Discussion
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Minor tweak for translation:update command

This fixes #10605. I didn't find any occurrence directly related to that issue ... but I propose to do this minor tweak.

Commits
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c01be3b Minor tweak for translation:update command

Author: javiereguiluz

translation.rst

@@ -351,7 +351,7 @@ with these tasks:
 
 .. code-block:: terminal
 
-    # updates the French translation file with the missing strings found in app/Resources/ templates
+    # updates the French translation file with the missing strings found in templates/
     $ php bin/console translation:update --dump-messages --force fr
 
     # updates the English translation file with the missing strings found in AppBundle