Fix failing CI tests

[JohnAlbin]

In recent PRs, the CI tests are failing.

The logs show:

FILE: ...ome/runner/drupal/web/modules/next/src/Form/NextSettingsForm.php
----------------------------------------------------------------------
FOUND 1 ERROR AFFECTING 1 LINE
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 10 | ERROR | [x] Use statements should be sorted alphabetically. The
    |       |     first wrong one is
    |       |     Drupal\next\Plugin\ConfigurablePreviewUrlGeneratorInterface.
    |       |     (SlevomatCodingStandard.Namespaces.AlphabeticallySortedUses.IncorrectlyOrderedUses)
----------------------------------------------------------------------
PHPCBF CAN FIX THE 1 MARKED SNIFF VIOLATIONS AUTOMATICALLY

There might be additional failures, but the tests stop when the first error occurs.

[JohnAlbin]

There might be additional failures, but the tests stop when the first error occurs.

Turns out it's just the one fix needed to get tests running. All tests are passing in #541