Switch RPC on receiving error, or random selection of RPCs each tx/query

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Is your feature request related to a problem? Please describe.
When adding multiple RPCs into the config.toml, it doesn't do anything noticeable when the server receives an error such as

2024-05-20T18:02:50Z ERR failed to prepare the transaction error="post failed: Post \"https://rpc.noncompliant.network:443\": context deadline exceeded (Client.Timeout exceeded while awaiting headers)"
2024-05-20T18:02:50Z INF Preparing the transaction messages=1
2024-05-20T18:02:50Z INF Querying the account address=sent1cnp8cwxtkvuecjss7vcv32aa3kq9lkhmmgerem
2024-05-20T18:03:20Z ERR failed to prepare the transaction error="post failed: Post \"https://rpc.noncompliant.network:443\": context deadline exceeded (Client.Timeout exceeded while awaiting headers)"

Describe the solution you'd like
Upon receiving an RPC error, the dvpn-node software should rotate to the next RPC in the comma delineated list. This will help keep nodes online when one or more RPCs are failing.

Or, select RPCs at random from the comma delineated list in config.toml.