[UX] Add HTML5 Date Widget Support to Views Exposed Form

Description of the need

This is a follow up to https://github.com/backdrop/backdrop-issues/issues/4255 where it was agreed that views exposed form support would be a good addition that could follow at a later time.

As a site user I want to have an easy to use date widget when filtering a view So that I can easily filter dates on my mobile or tablet.

Proposed solution

Views exposed form would allow the HTML5 widget (added in 1.23.0) to be selected as the widget for exposed form filtering on a view that filters on a date field or date metadata.

Alternatives that have been considered

None

Additional information

Draft of feature description for Press Release (1 paragraph at most)

Backdrop now includes the ability to filter views on dates using an HTML5 date widget, which offers a much better user experience for mobile and tablet users in particular.