minor #17158 Typo fix (andyexeter)

This PR was submitted for the 6.1 branch but it was squashed and merged into the 4.4 branch instead.

Discussion
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Typo fix

"Secret" should be plural "Secrets" in this context.

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Commits
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9dfb4b5 Typo fix

Author: xabbuh

best_practices.rst

@@ -88,8 +88,10 @@ application behavior.
 :ref:`Use env vars in your project <config-env-vars>` to define these options
 and create multiple ``.env`` files to :ref:`configure env vars per environment <config-dot-env>`.
 
-Use Secret for Sensitive Information
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+.. _use-secret-for-sensitive-information:
+
+Use Secrets for Sensitive Information
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 When your application has sensitive configuration - like an API key - you should
 store those securely via :doc:`Symfony’s secrets management system </configuration/secrets>`.