minor #9469 Propose identical comparison (grelu)

This PR was submitted for the 4.0 branch but it was merged into the 2.7 branch instead (closes #9469).

Discussion
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Propose identical comparison

Hi,
I suggest this : the identical comparison is better compared to the eqal comparison.
Grégory

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Commits
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e095afb Propose identical comparison

Author: javiereguiluz

best_practices/security.rst

@@ -177,7 +177,7 @@ to the ``Post`` entity that checks if a given user is its author::
          */
         public function isAuthor(User $user = null)
         {
-            return $user && $user->getEmail() == $this->getAuthorEmail();
+            return $user && $user->getEmail() === $this->getAuthorEmail();
         }
     }