minor symfony#20861 Collect all deprecations with lint:twig command (RisingSunLight42)

This PR was merged into the 6.4 branch.

Discussion
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Collect all deprecations with lint:twig command

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This PR fix symfony#20840 by tweaking the docs to precise only the first deprecation found will be outputed by the command.

_It's my first PR, I hope everything is fine, don't hesitate to notify me of any incorrect wording / style, or anything else. I'd be happy to learn how to contribute better for my future contributions!_

fixes symfony#20840

Commits
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50b6ffd fix command explanation

Author: javiereguiluz

templates.rst

@@ -849,7 +849,8 @@ errors. It's useful to run it before deploying your application to production
     $ php bin/console lint:twig templates/email/
     $ php bin/console lint:twig templates/article/recent_list.html.twig
 
-    # you can also show the deprecated features used in your templates
+    # you can also show the first deprecated feature used in your templates
+    # as it shows only the first one found, you may need to run it until no more deprecations are found
     $ php bin/console lint:twig --show-deprecations templates/email/
 
 When running the linter inside `GitHub Actions`_, the output is automatically