git: openjdk/jdk-sandbox: json: JsonNumber.of(String) snippet and more tests

[duke]

Changeset: df2f25b9
Branch: json
Author:    Naoto Sato <naoto.sato at oracle.com>
Date:      2025-12-03 10:26:53 +0000
URL:       https://git.openjdk.org/jdk-sandbox/commit/df2f25b928fcadfc36a7ec40c3dfad7e1ed80550

JsonNumber.of(String) snippet and more tests

! src/java.base/share/classes/java/util/json/JsonNumber.java
! test/jdk/java/util/json/TestJsonNumber.java