remove unused files (#1785)

Author: sparrowDom

contracts/contracts/interfaces/IERC20Details.sol

@@ -12,7 +12,6 @@ import { IRateProvider } from "../../interfaces/balancer/IRateProvider.sol";
 import { VaultReentrancyLib } from "./VaultReentrancyLib.sol";
 import { IOracle } from "../../interfaces/IOracle.sol";
 import { IVault } from "../../interfaces/IVault.sol";
-import { IRETH } from "../../interfaces/IRETH.sol";
 import { IWstETH } from "../../interfaces/IWstETH.sol";
 import { IERC4626 } from "../../../lib/openzeppelin/interfaces/IERC4626.sol";
 import { StableMath } from "../../utils/StableMath.sol";