Support for Maps (Objects) in UI

[jbaker-dstl]

Currently, you can't create maps (objects) via the UI when configuring components. This is an issue for some components, such as the Machine Translation setting, which requires a map of settings (which could change so can't be specified in advance).

There is some support for this in JSON Schema and React Json Schema Forms, but no support in the theme we're currently using: rjsf-team/react-jsonschema-form#1927

When the above issue is addressed, we should be able to update our UI dependencies and resolve this issue.