Remove `DELETE_DEREF` bytecode instruction

Feature or enhancement

Proposal:

The DELETE_DEREF opcode can be removed and deletion implemented by the sequence:
LOAD_DEREF POP_TOP PUSH_NULL STORE_DEREF

This would free up an opcode, and, since deletion of non-locals variables is practically never used, there is no cost to doing this.

Has this already been discussed elsewhere?

This is a minor feature, which does not need previous discussion elsewhere

Linked PRs

• gh-148185

首先检查 DELETE_DEREF opcode 的处理以及关联的 PR gh-148185。确定受影响的 compiler 和 runtime 路径，然后验证删除 non-local 时使用了提议的指令序列，并且 DELETE_DEREF opcode 已被移除。