[Deliverable] Web3 RPC fallback for service nodes

[chair28980]

Summary

Enable fallback strategies for nwaku services nodes to access Web3 RPC APIs, to ensure that service nodes remain online and able to run RLN Relay and RLNaaS despite ETH RPC provider outage.

[fryorcraken]

@Ivansete-status is this done?

[Ivansete-status]

@fryorcraken - it is done from nwaku's perspective but we will need to adapt infra once we deploy the v0.36 in waku fleets: status-im/infra-waku#34 Once this PR is completed, we can consider this as done

[fryorcraken]

Agreed, let's deploy first.

[Ivansete-status]

We can consider this as completed because the following infra change had been achieved: status-im/infra-waku#34