Link to correct console in older versions of docs

## 📚 Documentation

It's useful to be able to try older versions in the console, e.g. at https://pyodide.org/en/0.20.0/console.html. When looking at an older version of documentation such as https://pyodide.org/en/0.20.0/, the link "Try Pyodide in a [REPL](https://pyodide.org/en/stable/console.html)" should link to the corresponding version, not the stable version.