Adding polygon hardfork warning banner (#1861)

content/site.json

@@ -14,7 +14,7 @@
       "link": "/profile"
     }
   ],
-  "announcement": "[Lock your OCEAN](https://df.oceandao.org/) to get veOCEAN, earn rewards and curate data.",
+  "announcement": "Polygon hardfork is happening 17 Jan 2023. There may be disruptions in the publishing and consuming of assets.",
   "warning": {
     "ctd": "Please note that Compute-to-Data is still in alpha phase."
   }

src/components/App/index.tsx

@@ -23,7 +23,7 @@ export default function App({
   return (
     <div className={styles.app}>
       {siteContent?.announcement !== '' && (
-        <AnnouncementBanner text={siteContent?.announcement} />
+        <AnnouncementBanner text={siteContent?.announcement} state="warning" />
       )}
       <Header />