Adding some formatting instructions for contributing (#626)

* init adding of formatting instructions

* Update developers/contributing/index.qmd

Co-authored-by: Penelope Yong <[email protected]>

* Update developers/contributing/index.qmd

Co-authored-by: Penelope Yong <[email protected]>

* Update Manifest.toml

* okay i'll just do it

---------

Co-authored-by: AoifeHughes <[email protected]>
Co-authored-by: Penelope Yong <[email protected]>
Co-authored-by: Markus Hauru <[email protected]>

Author: 4 people