[MEV Boost\Builder] Add a builder rest api client

[StefanBratanov]

PR Description

Implement the builder rest api per the spec https://ethereum.github.io/builder-specs/

Changes:

• Implemented RestExecutionBuilderClient (previously they were throwing unsupported operation exception)
• Deleted old schema objects and serialization classes, which were used for the builder web3j implementation
• Use a schemaDefinitionCache to access the json type definitions in the rest api client
• Added BuilderApiResponse class to wrap the json responses coming from the rest api
• Changed the BuilderExecutionClient to use the spec classes rather than internal ones
• Modified Web3JExecutionBuilderClient to throw deprecated exception and deleted its test (it will be removed fully in the upcoming PRs)

Fixed Issue(s)

related to #5396

Documentation

• I thought about documentation and added the doc-change-required label to this PR if updates are required.

Changelog

• I thought about adding a changelog entry, and added one if I deemed necessary.

[tbenr]

LGTM