Aero harvester contract

[PraneshASP]

Description:

Added a new contract AeroHarvester to harvest AERO token rewards from the Aerodrome AMM, swap it back to Wrapped Ether and send it to the vault contract. This is required for the Aerodrome AMO strategy.

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Contract change checklist:

• Code reviewed by 2 reviewers.
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• Unit tests pass
• Slither tests pass with no warning
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[github-actions]

	Warnings
⚠️	👀 This PR needs at least 2 reviewers

Generated by 🚫 dangerJS against f885605

[sparrowDom]

This shares a lot of code with the BaseHarvester. Can it be refactored so it only re-implements the things that are different?

[PraneshASP]

This shares a lot of code with the BaseHarvester. Can it be refactored so it only re-implements the things that are different?

I tried the same earlier, but the Base harvester seems to be more Ethereum focused as there are lot of internal functions to handle swaps with various platforms. if we want to refactor, there'll be a lot of breaking changes in the BaseHarvester contract. To keep things simple, I created a new harvester contract specific to Aero (base).

cc: @sparrowDom