minor #14488 More explication for return into execute command function (TheGarious)

This PR was squashed before being merged into the 4.4 branch.

Discussion
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More explication for return into execute command function

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Actually, for 5.2 branch, we have got an explication for return into execute function into Command file with new Constant. But for 4.4 we don't have this constant and not explication what is return 1.

Commits
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eef382c More explication for return into execute command function

Author: OskarStark

console.rst

@@ -45,9 +45,16 @@ want a command to create a user::
 
         protected function execute(InputInterface $input, OutputInterface $output)
         {
-            // ...
+            // ... put here the code to run in your command
+
+            // this method must return an integer number with the "exit status code"
+            // of the command.
 
+            // return this if there was no problem running the command
             return 0;
+
+            // or return this if some error happened during the execution
+            // return 1;
         }
     }