minor #12040 Update Doc : Symfony 4.3 - Swift Mailer (TheGarious)

This PR was merged into the 4.3 branch.

Discussion
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Update Doc : Symfony 4.3 - Swift Mailer

Review Example, erase HelloBundle architecture by templates architecture.

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f8d783b Update Doc : Symfony 4.3 - Swift Mailer

Author: javiereguiluz

email.rst

@@ -260,7 +260,8 @@ Now, suppose you're sending an email to ``recipient@example.com`` in a controlle
             ->setTo('recipient@example.com')
             ->setBody(
                 $this->renderView(
-                    'HelloBundle:Hello:email.txt.twig',
+                    // templates/hello/email.txt.twig
+                    'hello/email.txt.twig',
                     ['name' => $name]
                 )
             )