message: [node] add links to edge error messages
  Add links to some Edge errors.
  Follow up to:
diff: @@ -193,7 +193,7 @@ async function compileUserCode(entrypoint: string) {
  let edgeHandler = module.exports.default;
  if (!edgeHandler) {
  - throw new Error('No default export was found. Add a default export to handle requests.');
  + throw new Error('No default export was found. Add a default export to handle requests. Learn more: https://vercel.link/creating-edge-middleware');
  }
  let response = await edgeHandler(event.request, event);
  @@ -305,7 +305,7 @@ function parseRuntime(
  throw new Error(
  `Invalid function runtime "${runtime}" for "${entrypoint}". Valid runtimes are: ${JSON.stringify(
  validRuntimes
  - )}`
  + )}. Learn more: https://vercel.link/creating-edge-functions`
  );
  }
  