PR #17599 broke `yarn test-build-devtools`. (b6c423daadaa35da3f34048628df9635505eecb1 is not broken,  0cf22a56a18790ef34c71bef14f64695c0498619 is broken)
```
    Configuration error:
    
    Could not locate module shared/consoleWithStackDev mapped as:
    /Users/bvaughn/Documents/git/react/build/node_modules/shared/consoleWithStackDev.
    
    Please check your configuration for these entries:
    {
      "moduleNameMapper": {
        "/^shared\/([^\/]+)$/": "/Users/bvaughn/Documents/git/react/build/node_modules/shared/$1"
      },
      "resolver": null
    }
```
'use strict';
const {readdirSync, statSync} = require('fs');
const {join} = require('path');
const baseConfig = require('./config.base');
const packagesRoot = join(__dirname, '..', '..', 'packages');
const packages = readdirSync(packagesRoot).filter(dir => {
  if (dir.charAt(0) === '.') {
    return false;
  }
  const packagePath = join(packagesRoot, dir, 'package.json');
  return statSync(packagePath).isFile();