Fix .gitignore: stop tracking ignored files

backend/lib/openzeppelin-contracts/contracts/mocks/governance/GovernorWithParamsMock.sol

@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.0;
+
+import "../../governance/extensions/GovernorCountingSimple.sol";
+import "../../governance/extensions/GovernorVotes.sol";
+
+abstract contract GovernorWithParamsMock is GovernorVotes, GovernorCountingSimple {
+    event CountParams(uint256 uintParam, string strParam);
+
+    function quorum(uint256) public pure override returns (uint256) {
+        return 0;
+    }
+
+    function votingDelay() public pure override returns (uint256) {
+        return 4;
+    }
+
+    function votingPeriod() public pure override returns (uint256) {
+        return 16;
+    }
+
+    function _getVotes(
+        address account,
+        uint256 blockNumber,
+        bytes memory params
+    ) internal view override(Governor, GovernorVotes) returns (uint256) {
+        uint256 reduction = 0;
+        // If the user provides parameters, we reduce the voting weight by the amount of the integer param
+        if (params.length > 0) {
+            (reduction, ) = abi.decode(params, (uint256, string));
+        }
+        // reverts on overflow
+        return super._getVotes(account, blockNumber, params) - reduction;
+    }
+
+    function _countVote(
+        uint256 proposalId,
+        address account,
+        uint8 support,
+        uint256 weight,
+        bytes memory params
+    ) internal override(Governor, GovernorCountingSimple) {
+        if (params.length > 0) {
+            (uint256 _uintParam, string memory _strParam) = abi.decode(params, (uint256, string));
+            emit CountParams(_uintParam, _strParam);
+        }
+        return super._countVote(proposalId, account, support, weight, params);
+    }
+}