PWM node should only send 1 request to PWM service to get all the data instead of 4 separate requests

<img width="783" alt="Screen Shot 2024-01-23 at 12 51 42 PM" src="https://github.com/EdgePi-Cloud/edgepi-rpc-client-js/assets/32500790/19800c89-0c45-4355-9e71-267465ad5601">

This need to be fixed on both the client and server sides.