[multi-select-combo-box] Update to use native popover for the overlay element #9723
Description
Motivation
Related to #9719
The vaadin-multi-select-combo-box should set popover="manual" on the vaadin-multi-select-combo-box-overlay.
Proposed solution
- Keep
vaadin-multi-select-combo-box-overlayin shadow DOM and useexportpartsfor::part()styling - Add
<vaadin-multi-select-combo-box-scroller slot="overlay">to the light DOM instead of arenderer