bug #12454 Update guard_authentication.rst (orangevinz)

This PR was merged into the 4.3 branch.

Discussion
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Update guard_authentication.rst

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Commits
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6dc1027 Update guard_authentication.rst

Author: OskarStark

security/guard_authentication.rst

@@ -38,7 +38,7 @@ directly to your ``User`` class (the ``make:entity`` command is a good way to do
         // ...
 
     +     /**
-    +      * @ORM\Column(type="string", unique=true)
+    +      * @ORM\Column(type="string", unique=true, nullable=true)
     +      */
     +     private $apiToken;