Add Unit Tests for RpcServer Plugin

[Jim8y]

Summary or problem description
Neo plugins lack unit tests, thus we need to add unit tests for them. This issue is a plan of adding unit tests for RpcServer plugin.

Do you have any solution you want to propose?

• RpcServer Unit Tests: Blockchain [Neo Plugins UT] Add RpcServer Unit Tests Part Blockchain. #3339
• RpcServer Unit Tests: Node #3350
• RpcServer Unit Tests: SmartContract
• RpcServer Unit Tests: Wallet
• RpcServer Unit Tests: Utilities

Where in the software does this update applies to?

• Plugins

[Pathak-Akshat]

can i also contribute to this?

[cschuchardt88]

can i also contribute to this?

repo is open to anyone that wants to contribute. Start by creating your own PR.