bug #646 Use validator on interactive mode (yceruto)

This PR was merged into the master branch.

Discussion
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Use validator on interactive mode

Fixing invalid callable argument.

Commits
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3c4538d Use validator on interactive mode

src/Command/DeleteUserCommand.php

@@ -100,7 +100,7 @@ protected function interact(InputInterface $input, OutputInterface $output)
             '',
         ]);
 
-        $username = $this->io->ask('Username', null, [$this, 'usernameValidator']);
+        $username = $this->io->ask('Username', null, [$this->validator, 'validateUsername']);
         $input->setArgument('username', $username);
     }