fix: Parsing error for code blocks in list items

[D-Sketon]

What does it do?

fix #5423

Screenshots

It should work well

Pull request tasks

• Add test cases for the changes.
• Passed the CI test.

[github-actions]

How to test

git clone -b fix/codeblock https://github.com/D-Sketon/hexo.git
cd hexo
npm install
npm test

[coveralls]

Pull Request Test Coverage Report for Build 13287854607

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 1 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 99.462%

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Totals
Change from base Build 13287074755:	0.0%
Covered Lines:	9794
Relevant Lines:	9847

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💛 - Coveralls

[uiolee]

LGTM!