Update contribution link from markdown to website

- Changed the contribution guide link in the README.md from the markdown file to the corresponding section on the official website.
- This change ensures that the link remains stable and is not impacted by the frequent changes to Markdown files.

README.md

@@ -32,7 +32,7 @@ And here are links of other repositories:
 
 ## Contributing
 
-- Welcome to contribute to HugeGraph, please see [How to Contribute](https://github.com/apache/incubator-hugegraph/blob/master/CONTRIBUTING.md) for more information.
+- Welcome to contribute to HugeGraph, please see [How to Contribute](https://hugegraph.apache.org/docs/contribution-guidelines/contribute/) for more information.
 - Note: It's recommended to use [GitHub Desktop](https://desktop.github.com/) to greatly simplify the PR and commit process.
 - Thank you to all the people who already contributed to HugeGraph!