Resolve warnings against using Node.js 16

[fktn-k]

This PR has resolved the warnings against using GitHub Actions depending on Node.js 16.
For more information, visit the following links:

• https://github.blog/changelog/2023-09-22-github-actions-transitioning-from-node-16-to-node-20/
• https://github.blog/changelog/2024-01-12-code-scanning-deprecation-of-codeql-action-v2/

No other changes have been made in this PR.

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Pull Request Checklist

Read the CONTRIBUTING.md file for detailed information.

• [x] Changes are described in the pull request or in a referenced issue.
• [x] The test suite compiles and runs without any error.
• [x] The code coverage on your branch is 100%.
• [x] The documentation is updated if you added/changed a feature.

Please don't

• The C++11 support varies between different compilers and versions. Please note the list of supported compilers. Some compilers like GCC 4.7 (and earlier), Clang 3.3 (and earlier), or Microsoft Visual Studio 13.0 and earlier are known not to work due to missing or incomplete C++11 support. Please refrain from proposing changes that work around these compiler's limitations with #ifdefs or other means.
• Please refrain from proposing changes that would break YAML specifications. If you propose a conformant extension of YAML to be supported by the library, please motivate this extension.
• Please do not open pull requests that address multiple issues.

[coveralls]

coverage: 100.0%. remained the same when pulling 7d793fe957410059b2965a8b1414cc0c16c661b7 on resolve_warnings_against_used_github_actions into 3a001bc782753e57b5b2cd96cd64483826c30b62 on develop.