docs: Markdown text splitter failed to run

[ssssshql]

Checklist

• I added a very descriptive title to this issue.
• I included a link to the documentation page I am referring to (if applicable).

Issue with current documentation:

https://docs.langchain.com/oss/javascript/integrations/splitters/code_splitter#markdown

const markdownText = `
# 🦜️🔗 LangChain

⚡ Building applications with LLMs through composability ⚡

## What is LangChain?

# Hopefully this code block isn't split
LangChain is a framework for...

As an open-source project in a rapidly developing field, we are extremely open to contributions.
`;

const mdSplitter = RecursiveCharacterTextSplitter.fromLanguage(
    "markdown",
    { chunkSize: 60, chunkOverlap: 0 }
);
const mdDocs = mdSplitter.createDocuments([{ pageContent: markdownText }]);
console.log(mdDocs);

I returned an error when running the code provided in the document

Idea or request for content:

No response

[ssssshql]

I also found an error when running the example code in one place, and now I suspect that there is a problem with my dependent version?

I tried updating the dependencies, but the result was still the same