\Drupal::config returns null if the config isn't set

Problem/Motivation

Warning: in_array() expects parameter 2 to be array, null given in _pathologic_replace() (line 164 of modules/contrib/pathologic/pathologic.module)

       // Default value is ['http', 'https', 'files', 'internal']
       // "files" and "internal" are for Path Filter compatibility.
-      && !in_array($parts['scheme'], \Drupal::config('pathologic.settings')->get('scheme_whitelist'))
+      && !in_array($parts['scheme'], \Drupal::config('pathologic.settings')->get('scheme_whitelist') ?? [])
     )
     // Bail out if it looks like there's only a fragment part.
     || (isset($parts['fragment']) && count($parts) === 1)

Steps to reproduce

Install module and remove configuration.

Proposed resolution

Add the null coalescing operator so it will at least be an empty array.