docs(querying): add _params to api routes (#1463)

Author: nobkd

docs/content/3.guide/2.displaying/2.querying.md

@@ -147,6 +147,7 @@ The API root path `/api/_content/query` accepts query parameters such as:
 - `/api/_content/query?only=title`
 - `/api/_content/query?sort=size:1`
 - `/api/_content/query?without=body`
+- `/api/_content/query?_params={"where":{"_path":"/hello"},"without":["body"]}`
 
 ### Example