[hotfix] [docs] Link documentation contribution guide from CONTRIBUTING

Made-with: Cursor

Author: Local Dev

.github/CONTRIBUTING.md

@@ -8,4 +8,5 @@ To make the process smooth for the project *committers* (those who review and ac
 
 Please check out the [How to Contribute guide](https://flink.apache.org/contributing/how-to-contribute.html) to understand how contributions are made.
 A detailed explanation can be found in our [Contribute Code Guide](https://flink.apache.org/contributing/contribute-code.html) which also contains a list of coding guidelines that you should follow.
+Documentation-only changes are described in the [Documentation Contribution Guide](https://flink.apache.org/how-to-contribute/contribute-documentation/) (including how to build and preview docs under `docs/`).
 For pull requests, there is a [check list](PULL_REQUEST_TEMPLATE.md) with criteria taken from the How to Contribute Guide and the Coding Guidelines.