Update price-feed-exists.mdx

Author: optke3

pages/sui/price-feed-exists.mdx

@@ -10,7 +10,7 @@ import Examples from "../../components/Examples";
 
 Determine if a price feed for the given `price_identifier` exists.
 Returns `true` if there has been at least one on-chain update of this feed in the past.
-Note that a `false` answer may mean that the feed exists, but simply has never been updated on Aptos.
+Note that a `false` answer may mean that the feed exists, but simply has never been updated on Sui.
 In this case, you can invoke [update_price_feeds](update-price-feeds) to pull an update on-chain.
 
 <div className="mt-6 overflow-x-auto">