This changes the nesting style because some CI / CD systems do not allow moving to a directory above the checkout for the primary repo (`react-sdk` in this case). Part of https://github.com/vector-im/element-web/issues/12624
This replaces Riot with Element in various CI scripts, modules, parameters, etc. This _should_ be the last major rebranding pass (hopefully). Fixes https://github.com/vector-im/element-web/issues/14894