message: chore: fix sponsors from open collective
  * Fix sponsors from open collective
  Also added Silver and Bronze sponsors.
  Fixes
  * Update README.md
  only gold and above are listed here.
diff: @@ -130,20 +130,20 @@ Funds donated via Patreon goes directly to support Evan You's full-time work on
  </tbody>
  </table>
  -<h3 align="center">Sponsors via OpenCollective</h3>
  +<h3 align="center">Sponsors via <a href="https://opencollective.com/vuejs">Open Collective</a></h3>
  <h4 align="center">Platinum</h4>
  -<!-- <a href="https://opencollective.com/vuejs/platinumsponsor/0/website" target="_blank"><img src="https://opencollective.com/vuejs/platinumsponsor/0/avatar.svg"></a>
  -<a href="https://opencollective.com/vuejs/platinumsponsor/1/website" target="_blank"><img src="https://opencollective.com/vuejs/platinumsponsor/1/avatar.svg"></a> -->
  +<a href="https://opencollective.com/vuejs/tiers/platinumsponsors/0/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/platinumsponsors/0/avatar.svg"></a>
  +<a href="https://opencollective.com/vuejs/tiers/platinumsponsors/1/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/platinumsponsors/1/avatar.svg"></a> -->
  <h4 align="center">Gold</h4>
  -<a href="https://opencollective.com/vuejs/goldsponsor/0/website" target="_blank"><img src="https://opencollective.com/vuejs/goldsponsor/0/avatar.svg"></a>
  -<a href="https://opencollective.com/vuejs/goldsponsor/1/website" target="_blank"><img src="https://opencollective.com/vuejs/goldsponsor/1/avatar.svg"></a>
  -<a href="https://opencollective.com/vuejs/goldsponsor/2/website" target="_blank"><img src="https://opencollective.com/vuejs/goldsponsor/2/avatar.svg"></a>
  -<a href="https://opencollective.com/vuejs/goldsponsor/3/website" target="_blank"><img src="https://opencollective.com/vuejs/goldsponsor/3/avatar.svg"></a>
  -<a href="https://opencollective.com/vuejs/goldsponsor/4/website" target="_blank"><img src="https://opencollective.com/vuejs/goldsponsor/4
  +<a href="https://opencollective.com/vuejs/tiers/goldsponsors/0/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/goldsponsors/0/avatar.svg"></a>
  +<a href="https://opencollective.com/vuejs/tiers/goldsponsors/1/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/goldsponsors/1/avatar.svg"></a>
  +<a href="https://opencollective.com/vuejs/tiers/goldsponsors/2/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/goldsponsors/2/avatar.svg"></a>
  +<a href="https://opencollective.com/vuejs/tiers/goldsponsors/3/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/goldsponsors/3/avatar.svg"></a>
  +<a href="https://opencollective.com/vuejs/tiers/goldsponsors/4/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/goldsponsors/4
  /avatar.svg"></a>
  ---
  