Put wateruse back on develop - #923

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/cache@v4, actions/checkout@9a9194f87191a7e9055e3e9b95b8cfb13023bb08, actions/upload-artifact@v4, r-lib/actions/setup-pandoc@6012817847b5f064d0882d67a7b5e2ca6639afb2, r-lib/actions/setup-r@cdfe59f7d9ed0bc33451d5e5d5d9dde04246fa59. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/