add unsafe-allow immutable

Author: frangio

contracts/governance/extensions/GovernorVotes.sol

@@ -12,6 +12,7 @@ import {SafeCast} from "../../utils/math/SafeCast.sol";
  * @dev Extension of {Governor} for voting weight extraction from an {ERC20Votes} token, or since v4.5 an {ERC721Votes} token.
  */
 abstract contract GovernorVotes is Governor {
+    /// @custom:oz-upgrades-unsafe-allow state-variable-immutable
     IERC5805 public immutable token;
 
     constructor(IVotes tokenAddress) {