chore: update sponsors (#2762)

Author: vue-bot

themes/vue/_config.yml

@@ -27,7 +27,8 @@ platinum_sponsors:
   - url: 'https://www.storyblok.com'
     img: storyblok.png
     name: Storyblok
-  - url: 'https://ionicframework.com/'
+  - url: >-
+      https://ionicframework.com/vue?utm_source=partner&utm_medium=referral&utm_campaign=vuesponsorship&utm_content=vuedocs
     img: ionic.png
     name: Ionic
 gold_sponsors: