Update .doc/connecting.asciidoc

Co-authored-by: István Zoltán Szabó <istvan.szabo@elastic.co>

Author: Anaethelion

.doc/connecting.asciidoc

@@ -64,7 +64,7 @@ es, err := elasticsearch.NewClient(cfg)
 [[compatibility-mode]]
 ==== Compatibility Mode
 
-Elasticsearch server 8.0 introduces a new compatibility mode allowing for a smoother transition from 7 to 8.
+{es} server 8.0 introduces a compatibility mode allowing for a smoother transition from 7 to 8.
 Using the compatibility mode, the client sends versioned headers with each request instructing the server on the expected behaviour.
 ------------------------------------
 Content-Type: application/vnd.elasticsearch+json; compatible-with=7