EVM-475 Create a Relayer microservice

[igorcrevar]

Description

Base PR for all other PRs related to the account abstraction

Sub-tasks:

• HTTP endpoint: (RFC-195).
• Pool of sorted transactions.
• Relay AA transactions as Ethereum transactions.
• Integration with smart contract
• E2E test

Changes include

• 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)

Breaking changes

Please complete this section if any breaking changes have been made, otherwise delete it

Checklist

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

Testing

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

[igorcrevar]

opAuth does not implement latest EIP3074 specification.
It works with current implementation of smart contract although it is not aligned with the latest specification like I mentioned above.
#1291 (comment)
https://github.com/maticnetwork/bor/commits/poleary/wip-eip-3074