Add page-alias to CALL subquery page (neo4j#1127)

Author: JPryce-Aklundh

modules/ROOT/pages/subqueries/call-subquery.adoc

@@ -1,5 +1,6 @@
 = CALL subqueries
 :description: This page describes how to use Cypher's `CALL` subquery.
+:page-aliases: clauses/call-subquery.adoc
 
 The `CALL` clause can be used to invoke subqueries that execute operations within a defined scope, thereby optimizing data handling and query efficiency. 
 Unlike other subqueries in Cypher, `CALL` subqueries can be used to perform changes to the database (e.g. xref:clauses/create.adoc[] new nodes).