minor #17577 chore: Add missing semicolon (TheKhanj)

This PR was submitted for the 6.2 branch but it was merged into the 5.4 branch instead.

Discussion
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chore: Add missing semicolon

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Commits
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836a973 chore: Add missing semicolon

Author: javiereguiluz

components/dependency_injection.rst

@@ -300,6 +300,7 @@ config files:
             $services = $container->services();
             $services->set('mailer', 'Mailer')
                 ->args(['%mailer.transport%'])
+            ;
 
             $services->set('mailer', 'Mailer')
                 // the param() method was introduced in Symfony 5.2.