feat: upgrade to use node 20 runtime and bump checkout action to v4

[chenrui333]

Description:

Node12 was deleted from runner. Node20 was added to Actions Runner on v2.308.0. Node16 has en end of life on 11 Sep 2023.

This PR updates the default runtime to node20, rather then node16

relates to https://github.com/actions/runner/pull/2732

Related issue: N/A

Check list:

• [ ] Mark if documentation changes are required.
• [ ] Mark if tests were added or updated to cover the changes.

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needs a major version bump after the PR merge

[chenrui333]

anything blocking the merge of this? Thanks!

[chenrui333]

@marko-zivic-93 thanks for the PR merge, can we make a new major release with it? 🙏

[FreeMason9224]

chenrui333:node20-runtime