Implement listen key validity period

[PAID Ticket rules](https://github.com/singlesly/bingx-api/wiki/Paid-tickets)  


**Price**: 10$  
  
**Acceptance criteria**:
- [ ] Endpoint class described
- [ ] ListenKeyService contains method
- [ ] Unit tests

Implement this [endpoint](https://bingx-api.github.io/docs/#/swapV2/listen-key.html#extend%20Listen%20Key%20Validity%20period)