This attempts to converge all our modals on the new modal component while changing their designs as little as possible. This should reduce the bundle size a bit and make the app generally feel like it's converging on the new designs, even though individual modals still remain to be revamped.
by fixing the cause rather than the symptom: this upgrades the code to use the new, recommended JSX transform mode of React 17+, which no longer requires you to import React manually just to write JSX.
This is an Element project (in the vector-im repo) so the Copyright
should be for New Vector: it was incorrectly attributed to the
foundation for some files (and some files were missing headers).
