[pickers] Open picker when clicking Space on field

[LukasTy]

Created from: #14587 (comment).

We are closely following the guidelines of https://www.w3.org/WAI/ARIA/apg/patterns/dialog-modal/examples/datepicker-dialog/ but native date input element does indeed open on Space click.

Search keywords:

[LukasTy]

• Should be worked after [fields] Move the logic of the fields opening to be in the field instead of in the picker #14787 is done.
• Look into applying it on the v7 (input) behavior.
• Test with playwright and @testing-library/user-event to see if entering "2022 04 17" causes the spaces to open the picker
  • if that's a problem, consider relying on the search query (if it not empty - do not open on Space click)