Symfony version(s) affected

6.2.0

Description

On my environment the $_SERVER['SHELL'] is not set by some reason.
When I run console completion the following error message shows up.

Detected shell "", which is not supported by Symfony shell completion (supported shells: "bash", "fish", "zsh").

How to reproduce

console completion ''

Possible Solution

Change wording for the case when SHELL has not been guessed.

Additional Context

No response