Add support for better client version details

[zivkovicmilos]

Description

This PR resolves a pending issue that doesn't return proper chain information on the client version.

It removes the base GET endpoint to the JSON-RPC layer, as it's not by the standard, nor should it be supported. Users should use the web3_clientVersion endpoint instead, that is outlined in the specification.

Changes include

• [x] Bugfix (non-breaking change that solves an issue)
• [ ] Hotfix (change that solves an urgent issue, and requires immediate attention)
• [ ] New feature (non-breaking change that adds functionality)
• [ ] Breaking change (change that is not backwards-compatible and/or changes current functionality)

Checklist

• [x] I have assigned this PR to myself
• [x] I have added at least 1 reviewer
• [x] I have added the relevant labels
• [ ] I have updated the official documentation
• [x] I have added sufficient documentation in code

Testing

• [x] I have tested this code with the official test suite
• [ ] I have tested this code manually

Additional comments

Fixes EDGE-709