message: [next] Handle output location
  Ensures output location is handled x-ref: [slack thread](https://vercel.slack.com/archives/C04DUD7EB1B/p1671473159350219?thread_ts=1671467623.309669&cid=C04DUD7EB1B)
diff: @@ -24,6 +24,7 @@ import {
  PrepareCache,
  NodejsLambda,
  BuildResultV2Typical as BuildResult,
  + BuildResultBuildOutput,
  } from '@vercel/build-utils';
  import { Route, RouteWithHandle, RouteWithSrc } from '@vercel/routing-utils';
  import {
  @@ -454,6 +455,24 @@ export const build: BuildV2 = async ({
  }
  debug('build command exited');
  + let buildOutputVersion: undefined | number;
  +
  + try {
  + const data = await readJSON(
  + path.join(outputDirectory, 'output/config.json')
  + );
  + buildOutputVersion = data.version;
  + } catch (_) {
  + // tolerate for older versions
  + }
  +
  + if (buildOutputVersion) {
  + return {
  + buildOutputPath: outputDirectory,
  + buildOutputVersion,
  + } as BuildResultBuildOutput;
  + }
  +
  let appMountPrefixNoTrailingSlash = path.posix
  .join('/', entryDirectory)
  .replace(/\/+$/, '');
  