Add warning that there is no replacement

Co-authored-by: Florentin Dörre <florentin.dorre@neotechnology.com>

Author: soerenreichardt

doc/modules/ROOT/pages/management-ops/graph-reads/read-with-cypher.adoc

@@ -3,6 +3,11 @@
 :description: This chapter explains how to execute Cypher queries on named graphs in the Neo4j Graph Data Science library.
 :page-aliases: management-ops/create-cypher-db, management-ops/graph-reads/create-cypher-db
 
+[WARNING]
+--
+This page describes running cypher queries on an in-memory graph which is deprecated and will be removed.
+There will be no replacement for this feature.
+--
 
 include::partial$/operations-reference/alpha-note.adoc[]