Challenge 2: Fix submodule dependencies

[MattPereira]

Fixes #24

Summary

• Removed all submodules except for cellar-contracts since that's all we need for this challenge. This branch is not dependent on yearn-vaults and @solmate is handled by the following remapping:

@solmate/=lib/cellar-contracts/lib/solmate/src

• Moved the test folder to root directory because that's where foundry looks for it by default unless you specify otherwise in the foundry.toml. Also may be better practice and easier to find tests if test folder is located at root level of foundry project.

• Removed all the remappings from foundry.toml to keep all of the remapping logic in one place: remappings.txt

Tips for local review of this PR

• test/AuraERC4626Adaptor.t.sol is hardcoded to require an env var with the name MAINNET_RPC_URL so you will want to add that to your .env file
• You may have to remove all of the other submodules completely which I did by manually deleting them from lib/

Proof Test Runs with this PR

About the Failing Checks

1. solidity job is failing because prettier formatting on files that are unchanged by this PR. Its actually not complaining about test/AuraERC4626Adaptor.t.sol because my prettier hit that file with my auto format on save
   

2. Foundry Project check is failing because it cant find etherescan api key in environment where github workflow is running
   

3. commits job is failing because it doesn't like my commit messages? 😢
   

[steve0xp]

Awesome job @MattPereira. Very well detailed work, and the screenshots and walk through were very much appreciated.

I have all tests passing from the test file when specifying to look at the solutions file: import {AuraERC4626Adaptor} from "src/Solutions/AuraERC4626Adaptor.sol"; vs the test file from the "student" at src/AuraERC4626Adaptor.sol.

I think that all the other errors that you described are going to be sorted through as we go into the next step of bringing everything into SE-2, so let's merge this to the branch and move forward!