minor #1177 Replaced return 0 with return Command::SUCCESS (Coderberg)

This PR was merged into the main branch.

Discussion
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Replaced `return 0` with `return Command::SUCCESS`

Commits
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0020dc5 Replaced `return 0` with `return Command::SUCCESS`

Author: javiereguiluz

src/Command/AddUserCommand.php

@@ -204,7 +204,7 @@ protected function execute(InputInterface $input, OutputInterface $output): int
             $this->io->comment(sprintf('New user database id: %d / Elapsed time: %.2f ms / Consumed memory: %.2f MB', $user->getId(), $event->getDuration(), $event->getMemory() / (1024 ** 2)));
         }
 
-        return 0;
+        return Command::SUCCESS;
     }
 
     private function validateUserData($username, $plainPassword, $email, $fullName): void

src/Command/DeleteUserCommand.php

@@ -127,6 +127,6 @@ protected function execute(InputInterface $input, OutputInterface $output): int
 
         $this->io->success(sprintf('User "%s" (ID: %d, email: %s) was successfully deleted.', $user->getUsername(), $userId, $user->getEmail()));
 
-        return 0;
+        return Command::SUCCESS;
     }
 }

src/Command/ListUsersCommand.php

@@ -127,7 +127,7 @@ protected function execute(InputInterface $input, OutputInterface $output): int
             $this->sendReport($usersAsATable, $email);
         }
 
-        return 0;
+        return Command::SUCCESS;
     }
 
     /**