doc: Update a confusing sentence about SQL/JSON

Author: Liudmila Mantrova <l.mantrova@postgrespro.ru>
Reported-by: Jeff Janes <jeff.janes@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAMkU%3D1wP-SO4KpiLxHJuPezTJCmK%3DJqefLXrr3eXFO7Qku%2BtMg%40mail.gmail.com

doc/src/sgml/json.sgml

@@ -641,8 +641,7 @@ SELECT jdoc->'guid', jdoc->'name' FROM api WHERE jdoc @> '{"tags": ["qu
   </para>
 
   <para>
-   The SQL/JSON path language is fully integrated into the SQL engine:
-   the semantics of its predicates and operators generally follow SQL.
+   The semantics of SQL/JSON path predicates and operators generally follow SQL.
    At the same time, to provide a most natural way of working with JSON data,
    SQL/JSON path syntax uses some of the JavaScript conventions:
   </para>