minor #20652 Explain how translation messages are merged among bundles (mpdude)

This PR was merged into the 6.4 branch.

Discussion
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Explain how translation messages are merged among bundles

This adds a detail about how messages are merged when more than one bundle provides a translation for a single message key.

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ac4a5f7 Explain how translation messages are merged among bundles

Author: javiereguiluz

translation.rst

@@ -497,7 +497,9 @@ Symfony looks for message files (i.e. translations) in the following default loc
   ``Resources/translations/`` directory, which is no longer recommended for bundles).
 
 The locations are listed here with the highest priority first. That is, you can
-override the translation messages of a bundle in the first directory.
+override the translation messages of a bundle in the first directory. Bundles are processed
+in the order they are given in the ``config/bundles.php`` file, so bundles listed first have
+higher priority.
 
 The override mechanism works at a key level: only the overridden keys need
 to be listed in a higher priority message file. When a key is not found