[RFR] Migrate export button

[fzaninotto]

As expected in #3623, using the new hooks changes the signature of the exporter function, but for the best.

-const exportComments = (data, fetchRelaterRecords, dispatch) => {
+const exportComments = (data, fetchRelaterRecords, dataProvider) => {
    // ...
}

This is a small BC break, because using the dispatch parameter in the exporter function was really cumbersome, and I doubt anyone has ever used it.

Also, people wishing to customize the export more deeply (with custom side effects, etc) can easily write their own. Here is the simplified version of the ExportButton component:

import {
    downloadCSV,
    useDataProvider,
    useNotify,
    GET_LIST,
} from 'react-admin';
import jsonExport from 'jsonexport/dist';

const ExportButton = ({ sort, filter, maxResults = 1000, resource }) => {
    const dataProvider = useDataProvider();
    const notify = useNotify();
    const payload = { sort, filter, pagination: { page: 1, perPage: maxResults }}
    const handleClick = dataProvider(GET_LIST, resource, payload)
        .then(({ data }) => jsonExport(data, (err, csv) => downloadCSV(csv, resource)))
        .catch(error => notify('ra.notification.http_error', 'warning'));

    return (
        <Button
            label="Export"
            onClick={handleClick}
        />
    );
};

Closes #3623

[djhi]

Much nicer indeed 👍