Fix PHP 8.4 implicitly nullable parameter deprecation in MaestroWebformTask

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Problem/Motivation

On PHP 8.4, loading Maestro’s workflow editor produces the following deprecation warning:

MaestroWebformTask::__construct(): Implicitly marking parameter $configuration as nullable is deprecated, the explicit nullable type must be used instead.

The constructor in modules/maestro_webform/src/Plugin/EngineTasks/MaestroWebformTask.php declares an array parameter with a default value of NULL:

public function __construct(array $configuration = NULL)

Proposed resolution

Explicitly declare the parameter nullable:

public function __construct(?array $configuration = NULL)

Update the corresponding PHPDoc from @param array to @param array|null.

This preserves existing behaviour: the constructor continues to accept an array or NULL.

Remaining tasks

• Review the change.
• Verify the workflow editor loads on PHP 8.4 without this deprecation warning.
• Verify the constructor accepts omitted configuration, explicit NULL, and an array containing process and queue IDs.
• Run PHP syntax validation.

User interface changes

The PHP deprecation warning no longer appears above the workflow editor when error display is enabled.

API changes

The constructor parameter explicitly declares its existing nullable behaviour. Accepted inputs remain unchanged.

Data model changes

None. No database updates, configuration changes, or update hooks are required. Rebuild Drupal caches after applying the change.

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