display correct missing route in 404 page (#2083)

## What's the purpose of this pull request?

display the correct missing URL when hitting a 404 page
#2064

## How it works?

use `asPath` which Next provides as the alias for that particular 404
response

## How to test it?

1. visit path which doesn't exist
2. see that the URL is displayed in the body of the page

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packages/core/src/pages/404.tsx

@@ -12,11 +12,10 @@ import EmptyState from 'src/components/sections/EmptyState'
 
 const useErrorState = () => {
   const router = useRouter()
-  const { from } = router.query
-  const { pathname } = router
+  const { pathname, asPath } = router
 
   return {
-    fromUrl: from ?? pathname,
+    fromUrl: asPath ?? pathname,
   }
 }