Docs: Fix deprecation warning in Asciidoctor

Fix a deprecation warning that wasn't rendering correctly in
asciidoctor. This one needed to be explicitly marked as an inline macro
because it is on its own line and it needed to have its text escaped
because it contained a `,`. It also was missing explanitory text for
what the setting was.

docs/plugins/repository-gcs.asciidoc

@@ -245,7 +245,8 @@ include::repository-shared-settings.asciidoc[]
 
 `application_name`::
 
-    deprecated[7.0.0, This setting is now defined in the <<repository-gcs-client, client settings>>]
+    deprecated:[6.3.0, "This setting is now defined in the <<repository-gcs-client, client settings>>."]
+    Name used by the client when it uses the Google Cloud Storage service.
 
 [[repository-gcs-bucket-permission]]
 ===== Recommended Bucket Permission