git: openjdk/jdk-sandbox: json: maintain insertion order

[duke]

Changeset: 418659a6
Branch: json
Author:    Justin Lu <justin.lu at oracle.com>
Date:      2025-03-07 10:20:56 +0000
URL:       https://git.openjdk.org/jdk-sandbox/commit/418659a68c0b7e6e87475892553f0ab59f1a0ade

maintain insertion order

! src/java.base/share/classes/java/util/json/JsonObjectImpl.java
! test/jdk/java/util/json/TestJsonObject.java