[ssh_hardening] AllowUsers passing user with brackets

[Dan-Sun]

Description

I use the the variable ssh_allow_users for a debian system:

ssh_allow_users: 
      - "{{ ansible_user }}"
      - user2
      - user3

The outcome is AllowUsers ['user1', 'user2', 'user3'] which doesn't work on my end.
It would work like AllowUsers user1 user2 user3.

Reproduction steps

Add the variable:

ssh_allow_users: 
      - "{{ ansible_user }}"
      - user2
      - user3

### Current Behavior

The out come is `AllowUsers ['user1', 'user2', 'user3']` which doesn't work on my side.

### Expected Behavior

It would work like `AllowUsers user1 user2 user3`.

### OS / Environment

The target is a fresh installed Debian minimal system. Coming from an Arch system.

### Ansible Version

```Shell
2.18.1

Collection Version

10.2.0

Additional information

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