Returns whether the worker is eligible to take advances (On-Demand Pay).

When eligible is false, the worker cannot take new advances.

When eligible is true, the worker is permitted to take advances.

In sandbox, the following worker IDs are available to return a static response:

• ELIGIBLE_SAMPLE_WORKER_ID: Returns a response with eligible = true.
• INELIGIBLE_SAMPLE_WORKER_ID: Returns a response with eligible = false.
• NOT_FOUND_SAMPLE_WORKER_ID: Returns a 404 error indicating the worker was not found.