bug #4350 Removed extra parenthesis (sivolobov)

This PR was merged into the 2.3 branch.

Discussion
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Removed extra parenthesis

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?  | no
| Applies to    | all versions
| Fixed tickets | no tickets

Commits
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6e9e1e6 Removed extra parenthesis

best_practices/business-logic.rst

@@ -104,7 +104,7 @@ Now you can use the custom slugger in any controller class, such as the
         // ...
 
         if ($form->isSubmitted() && $form->isValid()) {
-            $slug = $this->get('slugger')->slugify($post->getTitle()));
+            $slug = $this->get('slugger')->slugify($post->getTitle());
             $post->setSlug($slug);
 
             // ...