Arithmetic overflow bug in `maxDeposit` and `maxMint` functions in Aave V3 wrapper

[duckception]

Hey, there's an arithmetic overflow bug in the maxDeposit and maxMint functions in the AaveV3ERC4626.sol contract, which makes them revert in certain situations. This breaks the ERC-4626 standard. See this issue for more in-depth details and a proposed fix.