Update translation.rst

I do think this website need more visibility 
Is it present elsewhere ? Or better to add elsewhere?

As usual, feel free to close if not relevant

Author: 94noni

translation.rst

@@ -1668,6 +1668,10 @@ no longer needs to be a painful process and boils down to these steps:
 * Manage the user's locale, which is stored on the request, but can also
   be set on the user's session.
 
+.. tip::
+
+    You can help us translate Symfony itself and be a contributor. Visit https://symfony-translations.nyholm.tech/ to get going. Thank you.
+
 Learn more
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