[Fix] Keep using node 16

[HAOCHENYE]

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Motivation

1. Allow node 16 in actions: checkout@v3 using node20 instead of node16 actions/checkout#1809
2. Fix mypy-mirror in pre-commit hook Pre-commit fails to run when typed_ast needs to be built. pre-commit/pre-commit#2850

Modification

Please briefly describe what modification is made in this PR.

BC-breaking (Optional)

Does the modification introduce changes that break the backward-compatibility of the downstream repositories?
If so, please describe how it breaks the compatibility and how the downstream projects should modify their code to keep compatibility with this PR.

Use cases (Optional)

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Checklist

Before PR:

• I have read and followed the workflow indicated in the CONTRIBUTING.md to create this PR.
• Pre-commit or linting tools indicated in CONTRIBUTING.md are used to fix the potential lint issues.
• Bug fixes are covered by unit tests, the case that causes the bug should be added in the unit tests.
• New functionalities are covered by complete unit tests. If not, please add more unit test to ensure the correctness.
• The documentation has been modified accordingly, including docstring or example tutorials.

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[zhouzaida]

Can we use the Node20?