drop vercel.json — we do not deploy on Vercel

We do not deploy on Vercel. Inherited from upstream; removed here because this fork's deploys are native.

vercel.json

@@ -1,24 +0,0 @@
-{
-  "$schema": "https://openapi.vercel.sh/vercel.json",
-  "version": 2,
-
-  "rewrites": [
-    {
-      "source": "/(api|organization-avatar|avatar)/(.*)",
-      "destination": "https://sentry.io/$1/$2"
-    },
-    {
-      "source": "/region/(\\w+)/(.*)",
-      "destination": "https://$1.sentry.io/$2"
-    },
-    { "source": "/_assets/(.*)", "destination": "/$1" },
-    { "source": "/(.*)", "destination": "/index.html" }
-  ],
-  "headers": [
-    {
-      "source": "/api/(.*)",
-      "headers": [{ "key": "Referer", "value": "https://sentry.io/" }]
-    }
-  ],
-  "github": { "silent": true }
-}