fix: The dependencies for the default container must always be an array, never null.

[cafuego]

Because when it's null trying to save the settings form results in a WSOD and nobody wants that.

Refs: RWR-382

[github-actions]

Build output

Composer Validate `success`

PHP Lint `success`

Docker Build `success`

Environment Setup `success`

Site Install `success`

PHP Code Sniffer `success`

Software Versions

```PHP 8.2.10 (cli) (built: Sep 2 2023 06:59:22) (NTS)
Copyright (c) The PHP Group
Zend Engine v4.2.10, Copyright (c) Zend Technologies
with Zend OPcache v8.2.10, Copyright (c), by Zend Technologies
with Xdebug v3.2.1, Copyright (c) 2002-2023, by Derick Rethans
Composer version 2.6.4 2023-09-29 10:54:46
```

Pusher: @attiks, Action: `pull_request`, Workflow: `Run tests``;

[rupl]

The edit URL should be greedier but aside from that 👍🏼

[github-actions]

Coverage Report

Totals
Statements:	46.3% ( 1565 / 3380 )
Methods:	26.14% ( 23 / 88 )
Lines:	46.84% ( 1542 / 3292 )