minor #17424 Typo (ThomasLandauer)

This PR was merged into the 5.4 branch.

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Typo

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ff1f333 Typo

Author: javiereguiluz

reference/configuration/security.rst

@@ -326,7 +326,7 @@ login_path
 **type**: ``string`` **default**: ``/login``
 
 This is the route or path that the user will be redirected to (unless ``use_forward``
-is set to ``true``) when they try to access a protected resource but isn't
+is set to ``true``) when they try to access a protected resource but aren't
 fully authenticated.
 
 This path **must** be accessible by a normal, unauthenticated user, else