Ensure consistency in feature file exports by aligning REST API behavior with UI exports

Description

Currently, when exporting a feature file via the REST API, the Test Set tag (label) is included in the file, even when exporting from an individual Test. However, this tag should only be present when exporting from a Test Set.

In contrast, when exporting from the UI, the feature file correctly only includes the Test tag without the Test Set tag.

To ensure consistency across export methods, the REST API should support an option to control the inclusion of the Test Set tag.