
 function setWinner(uint256 _winningOutcome) internal {
...
    uint256 _blockTimestamp = uint32(block.timestamp);
    require(_blockTimestamp <= type(uint32).max, "Overflow");


//Testcode:
pragma solidity 0.8.7;
contract Convert {
   uint256 public a = uint256( type(uint32).max )+1; // a==4294967296
   uint32  public b = uint32(a); // b==0
   uint256 public c = uint32(a); // c==0
}
    require( block.timestamp <= type(uint32).max, "Overflow");
    uint256 _blockTimestamp = uint32(block.timestamp);
