Feat/injective spot with delegation #6493

Summary

Implementation of a pure Python (no gateway required) Injective spot markets connector to be used with delegated accounts. Developer: Injective Labs team (https://injectivelabs.org/) Documentation: https://api.injective.exchange/

Rationale

With the intention of reducing issues when submitting transactions to the chain due to repeated or inconsistent sequence numbers we have created a new spot connector supporting delegated accounts. Delegated accounts means that the user will have the funds in one account (known as portfolio account or granter account) but all trading messages and transactions sent to the chain will be signed with a different account (known as the trading account or grantee account). To support this functionality the connector uses the Injective authz module. With the new connector the user can have many Hummingbot instances trading using the same funds (the same portfolio account) but with a different trading account for each bot, ensuring that each Hummingbot instance will use independent accounts when sending transactions to the chain, and hence independent sequence numbers (eliminating with this the sequence number mismatch issues).

Github Link

https://github.com/hummingbot/hummingbot/pull/6493