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

[lurui1997]

What is the purpose of the change

Point new contributors from .github/CONTRIBUTING.md to the official Documentation Contribution Guide so doc-only work (preview under docs/, JIRA expectations) is discoverable next to the code contribution links.

Brief change log

• Added one sentence and link to https://flink.apache.org/how-to-contribute/contribute-documentation/

Verifying this change

This change is a trivial rework / code cleanup without any test coverage.

Does this pull request potentially affect one of the following parts:

• Dependencies: no
• The public API: no
• The serializers: no
• The runtime per-record code paths: no
• Deployment or recovery: no
• The S3 file system connector: no

Documentation

• Does this pull request introduce a new feature? no

Made with Cursor

[lurui1997]

Submitted as a [hotfix] [docs] change per .github/PULL_REQUEST_TEMPLATE.md (no JIRA for trivial doc onboarding tweaks). Happy to fold into a FLINK ticket if a committer prefers.

[flinkbot]

CI report:

• 1467ee4 Azure: SUCCESS

Bot commands

The @flinkbot bot supports the following commands:

• @flinkbot run azure re-run the last Azure build

[snuyanzin]

didn't get what is the reason to have it separate?
The link above

Please check out the How to Contribute guide to understand how contributions are made.

leads to the page with all kinds of contributions including documentation, site, code, code review etc...
If we add it here then finally we will come up to just a copy of that page in this place