Update material-ui in integration app

This only really matters for maintenance and security alert purposes, it doesn't affect the code shipped in the library. An attempt to bring MUI up from `0.x` to `4.x` was started on `upgrade-material-ui`. All the mechanical things have been done there, but now there are issues that require logic changes to fix.

AC:
* fix the UI in `upgrade-material-ui` up so it functions and integration tests pass
* (optional) migrate from MUI v4 to MUI v5 from that point