[Chore] Use ReactNode instead of ReactElement where applicable

[jonathanarnault]

Depends on #10996

Problem

A lot of RA components expect a ReactElement where a ReactNode could be used.

Solution

Replace ReactElement with ReactNode where applicable.

How To Test

N/A

Additional Checks

• The PR targets master for a bugfix or a documentation fix, or next for a feature
• The PR includes unit tests (if not possible, describe why)
• The PR includes one or several stories (if not possible, describe why)
• The documentation is up to date

Also, please make sure to read the contributing guidelines.

[djhi]

I think you missed the <Datagrid expand> prop as it takes a ReactNode too according to both the doc and JSDoc (https://github.com/marmelab/react-admin/pull/10998/files#diff-1458ac898ea2924cc9ba84a442d85a75980a77a4f53823799136600375603063R401)