Update TOC.yml

Author: wmwxwa

articles/cosmos-db/mongodb/vcore/TOC.yml

@@ -1,8 +1,8 @@
-- name: MongoDB vCore documentation
+- name: MongoDB (vCore) documentation
   href: index.yml
 - name: Overview
   items:
-    - name: What is Azure Cosmos DB for MongoDB vCore?
+    - name: What is Azure Cosmos DB for MongoDB (vCore)?
       href: introduction.md
     - name: FAQ
       href: faq.yml