chore: fixes gold / platinum sponsors on open collective (#7311)

Fixes opencollective/opencollective#777

Author: xdamman

Diff for: README.md

@@ -143,16 +143,16 @@ Funds donated via Patreon goes directly to support Evan You's full-time work on
 
 <h4 align="center">Platinum</h4>
 
-<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>
+<a href="https://opencollective.com/vuejs/tiers/platinum-sponsors/0/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/platinum-sponsors/0/avatar.svg"></a>
+<a href="https://opencollective.com/vuejs/tiers/platinum-sponsors/1/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/platinum-sponsors/1/avatar.svg"></a>
 
 <h4 align="center">Gold</h4>
 
-<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>
+<a href="https://opencollective.com/vuejs/tiers/gold-sponsors/0/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/gold-sponsors/0/avatar.svg"></a>
+<a href="https://opencollective.com/vuejs/tiers/gold-sponsors/1/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/gold-sponsors/1/avatar.svg"></a>
+<a href="https://opencollective.com/vuejs/tiers/gold-sponsors/2/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/gold-sponsors/2/avatar.svg"></a>
+<a href="https://opencollective.com/vuejs/tiers/gold-sponsors/3/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/gold-sponsors/3/avatar.svg"></a>
+<a href="https://opencollective.com/vuejs/tiers/gold-sponsors/4/website" target="_blank"><img src="https://opencollective.com/vuejs/tiers/gold-sponsors/4/avatar.svg"></a>
 
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