Optimize Math.max and SignedMath.max (#3679)

Co-authored-by: Daniel Liu <liudaniel@qq.com>

CHANGELOG.md

@@ -29,6 +29,7 @@
  * `Arrays`: Add `unsafeAccess` functions that allow reading and writing to an element in a storage array bypassing Solidity's "out-of-bounds" check. ([#3589](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3589))
  * `Strings`: optimize `toString`. ([#3573](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3573))
  * `Ownable2Step`: extension of `Ownable` that makes the ownership transfers a two step process. ([#3620](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3620))
+ * `Math` and `SignedMath`: optimize function `max` by using `>` instead of `>=`. ([#3679](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3679))
 
 ### Breaking changes
 

contracts/utils/math/Math.sol

@@ -17,7 +17,7 @@ library Math {
      * @dev Returns the largest of two numbers.
      */
     function max(uint256 a, uint256 b) internal pure returns (uint256) {
-        return a >= b ? a : b;
+        return a > b ? a : b;
     }
 
     /**

contracts/utils/math/SignedMath.sol

@@ -11,7 +11,7 @@ library SignedMath {
      * @dev Returns the largest of two signed numbers.
      */
     function max(int256 a, int256 b) internal pure returns (int256) {
-        return a >= b ? a : b;
+        return a > b ? a : b;
     }
 
     /**