minor #12854 Update password_migration.rst (atailouloute)

This PR was merged into the 4.4 branch.

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Update password_migration.rst

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f5bbc44 Update password_migration.rst

Author: xabbuh

security/password_migration.rst

@@ -188,7 +188,7 @@ Trigger Password Migration From a Custom Encoder
 If you're using a custom password encoder, you can trigger the password
 migration by returning ``true`` in the ``needsRehash()`` method::
 
-    // src/Security/UserProvider.php
+    // src/Security/CustomPasswordEncoder.php
     namespace App\Security;
 
     // ...