Remove unsued imported library "Math.sol" (#3605)

CHANGELOG.md

@@ -12,6 +12,7 @@
  * `ReentrancyGuard`: Reduce code size impact of the modifier by using internal functions. ([#3515](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3515))
  * `SafeCast`: optimize downcasting of signed integers. ([#3565](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3565))
  * `ERC20FlashMint`: add an internal `_flashFee` function for overriding. ([#3551](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3551))
+ * `VestingWallet`: remove unused library `Math.sol`. ([#3605](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3605))
 
 ### Compatibility Note
 

contracts/finance/VestingWallet.sol

@@ -5,7 +5,6 @@ pragma solidity ^0.8.0;
 import "../token/ERC20/utils/SafeERC20.sol";
 import "../utils/Address.sol";
 import "../utils/Context.sol";
-import "../utils/math/Math.sol";
 
 /**
  * @title VestingWallet