feat(storage): update compose sample to support deleteSourceObjects option

[nidhiii-27]

Update compose_file snippet to support deleteSourceObjects option.
Add corresponding integration tests.

[Generated-by: AI]

[gemini-code-assist]

Code Review

This pull request introduces a $deleteSourceObjects parameter to the compose_file function to allow deleting source objects after they are composed, along with corresponding test updates. However, the deleteSourceObjects option is not supported by the Bucket::compose() method or the underlying Cloud Storage API. You should instead explicitly delete the source objects in your code after a successful compose operation.

[gemini-code-assist]

The deleteSourceObjects option is not supported by the Google\Cloud\Storage\Bucket::compose() method or the underlying Cloud Storage Compose API. Passing this option will either be ignored or cause an API error, and the source objects will not be deleted.

To support this option, you should explicitly delete the source objects after a successful compose operation.

    $targetObject = $bucket->compose($objectsToCompose, $targetObjectName, [
        'destination' => [
            'contentType' => 'application/octet-stream'
        ]
    ]);

    if ($targetObject->exists()) {
        if ($deleteSourceObjects) {
            foreach ($objectsToCompose as $sourceObjectName) {
                $bucket->object($sourceObjectName)->delete();
            }
        }
        $deletionMessage = $deleteSourceObjects ? ' and the source objects were deleted' : '';
        printf(
            'New composite object %s was created by combining %s and %s%s',
            $targetObject->name(),
            $firstObjectName,
            $secondObjectName,
            $deletionMessage
        );
    }