6 files declare their use of Response in JSON-RPC 2.x

Handler.php in src/Handler.php

HttpController.php in src/Controller/HttpController.php

JsonRpcException.php in src/Exception/JsonRpcException.php

RpcResponseFactory.php in src/Shaper/RpcResponseFactory.php

SecondMethod.php in tests/modules/jsonrpc_test/src/Plugin/jsonrpc/Method/SecondMethod.php

ThirdMethod.php in tests/modules/jsonrpc_test/src/Plugin/jsonrpc/Method/ThirdMethod.php