remove luxon dependency in web

packages/web/components/templates/homeFeed/LibrarySearchBar.tsx

@@ -24,7 +24,10 @@ type LibraryFilter =
   | 'type:highlights'
   | `saved:${string}`
 
-const recentlySavedStartDate = DateTime.now().minus({ days: 7 }).toISODate()
+// get last week's date
+const recentlySavedStartDate = new Date(
+  new Date().getTime() - 7 * 24 * 60 * 60 * 1000
+).toLocaleDateString('en-US')
 
 const FOCUSED_BOXSHADOW = '0px 0px 2px 2px rgba(255, 234, 159, 0.56)'