### Pandas version checks - [X] I have checked that the issue still exists on the latest versions of the docs on `master` [here](https://pandas.pydata.org/docs/dev/) ### Location of the documentation https://github.com/pandas-dev/pandas/blob/master/.github/CONTRIBUTING.md ### Documentation problem The links "Test-driven development/code writing" and "Code standards" leads to not (anymore?) existing anchors on the docs. ### Suggested fix for documentation Either remove the links or fix them, possibly by re-inserting info about test-driven development/code writing and code standards.