title: Multiple versions of the same package in the yarn.lock file
body: <p>I see 3 different version of one package in the yarn.lock, for example:</p>
  
  <pre><code>angular@1.6:
    version "1.6.10"
    resolved "https://registry.yarnpkg.com/angular/-/angular-1.6.10.tgz#eed3080a34d29d0f681ff119b18ce294e3f74826"
    integrity sha512-PCZ5/hVdvPQiYyH0VwsPjrErPHRcITnaXxhksceOXgtJeesKHLA7KDu4X/yvcAi+1zdGgGF+9pDxkJvghXI9Wg==
  
  angular@&gt;=1.4.0, angular@^1.0.8:
    version "1.7.7"
    resolved "https://registry.yarnpkg.com/angular/-/angular-1.7.7.tgz#26bd87693deadcbd5944610a7a0463fc79a18803"
    integrity sha512-MH3JEGd8y/EkNCKJ8EV6Ch0j9X0rZTta/QVIDpBWaIdfh85/e5KO8+ZKgvWIb02MQuiS20pDFmMFlv4ZaLcLWg==
  
  angular@~1.2.0:
    version "1.2.32"
    resolved "https://registry.yarnpkg.com/angular/-/angular-1.2.32.tgz#df52625a5167919931418dda3a9208b9f5fa3db4"
    integrity sha1-31JiWlFnkZkxQY3aOpIIufX6PbQ=
  </code></pre>
  
  <p>Does that mean the final bundle contains all of them, otherwise how webpack knows which version to select? What is the best practice in the community to deal with that? I know about <code>--flat</code> option but there are thousands packages, it would take a while for me to select one for each. </p>