message: docs(nextjs-plugin): update how custom handlers should be used
diff: @@ -338,13 +338,15 @@ The custom handler needs to look something like this:
  const compat = require("next-aws-lambda");
  module.exports = page => {
  - const handler = (event, context, callback) => {
  + const handler = (event, context) => {
  // do any stuff you like
  // this makes sure the next page renders
  - compat(page)(event, context, callback);
  + const responsePromise = compat(page)(event, context);
  // do any other stuff you like
  +
  + return responsePromise;
  };
  return handler;
  };
  