How do I set HTTP response status code when i receive 500 Internal Error? 
I tried using below plugin:
const setHttpPlugin = {
        async requestDidStart() {
        return {
            async willSendResponse({ response }) {
                if (response?.errors?.[0]?.message === 'undefined') {
                    response.http.status = 418;
                }
            }
        };
        }
    };
    and called it when creating new ApolloServer (I am using "apollo-server": "^3.12.1" and "apollo-server-express": "^3.9.0").
    
1) How to get http headers ? 
2) How do I reset http header when i encounter 500.
PS: I can see the error.exceptions where I throw the GraphQL error code, but changing **http** **500** seems impossible.
    