git: openjdk/jdk-sandbox: classfile-api-dev-branch: simplified CodeImpl.SINGLETON_INSTRUCTIONS initialization

[Adam Sotona]

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Changeset: 16934bc0
Author:    Adam Sotona <asotona at openjdk.org>
Date:      2023-03-06 14:56:23 +0000
URL:       https://git.openjdk.org/jdk-sandbox/commit/16934bc05767bd587e19331ae83ca80c315c7200

simplified CodeImpl.SINGLETON_INSTRUCTIONS initialization

! src/java.base/share/classes/jdk/internal/classfile/impl/CodeImpl.java