fix(markdown): handle data uri correctly, close #1393

[Mister-Hope]

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• [ ] Read the Contributing Guidelines.
• [ ] Provide a description in this PR that addresses what the PR is solving. If this PR is going to solve an existing issue, please reference the issue (e.g. close #123).

What is the purpose of this pull request?

• [ ] Bug fix
• [ ] New feature
• [ ] Documentation update
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[meteorlxy]

@Mister-Hope Please resolve the CI error