minor #15062 Command naming conventions (danepowell)

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

Discussion
----------

Command naming conventions

This is a partial fix for symfony/symfony#36973, to be reviewed along with symfony/symfony#40387

Commits
-------

60f8569 Command naming conventions

Author: javiereguiluz

contributing/code/conventions.rst

@@ -234,3 +234,11 @@ of the impacted component:
 This task is mandatory and must be done in the same pull request.
 
 .. _`@-silencing operator`: https://www.php.net/manual/en/language.operators.errorcontrol.php
+
+Naming Commands and Options
+---------------------------
+
+Commands and their options should be named and described using the English
+imperative mood (i.e. 'run' instead of 'runs', 'list' instead of 'lists'). Using
+the imperative mood is concise and consistent with similar command-line
+interfaces (such as Unix man pages).