fix: don't show collection name as root

Author: erezrokah

example/content/pages/index.md

@@ -0,0 +1,3 @@
+---
+title: Root
+---

src/NestedCollection.js

@@ -68,9 +68,7 @@ const TreeNavLink = styled.div`
 `;
 
 const getNodeTitle = (node) => {
-  const title = node.isRoot
-    ? node.title
-    : node.children.find((c) => !c.isDir && c.title)?.title || node.title;
+  const title = node.children.find((c) => !c.isDir && c.title)?.title || node.title;
   return title;
 };