fix incorrect heading

Author: amalhotra-mdb

source/copilot.txt

@@ -32,7 +32,7 @@ Commands
 The ``/query`` command assists in generating queries from a natural
 language against a connected MongoDB cluster.
 
-:ref:`/query <vsce-copilot-schema>`
+:ref:`/schema <vsce-copilot-schema>`
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 The ``schema`` command provides schema information about collections in