Update doc to use encoded API key instead of tuple

Author: JoshMock

docs/guide/connecting.asciidoc

@@ -328,11 +328,11 @@ https://www.elastic.co/guide/en/elasticsearch/reference/current/security-api-cre
 ----
 from elasticsearch import Elasticsearch
 
-# Adds the HTTP header 'Authorization: ApiKey <base64 api_key.id:api_key.api_key>'
+# Adds the HTTP header 'Authorization: ApiKey encoded_api_key>'
 es = Elasticsearch(
     "https://localhost:9200",
     ca_certs="/path/to/http_ca.crt",
-    api_key=("api_key.id", "api_key.api_key")
+    api_key="encoded_api_key",
 )
 ----