Tooltip: consider adding support for rendering in legacy popover slot

[ciampo]

As noted in #47614 (comment), the recent refactor of Tooltip introduced a change to where the tooltip's contents render in the page.

Prior to the refactor, Tooltip was using Popover internally, and as a consequence, the tooltip's contents were rendered inside the matching <Popover.Slot />.

After the refactor, the tooltip's contents render in a new dom node added by ariakit.

As a consequence, we should understand:

• whether we should tweak the Tooltip component so that it renders in a Popover.Slot if there is a matching one (and in a new portal as fallback)
• what consequences would that have on the editor (see Popovers and other UI should not appear on top of modal dialog overlays #55894), superficially when tooltips are rendered inside other modal UI

[ciampo]

As per #56482, we should NOT have the Tooltip component render in the Popover.Slot by default.

At most, we could expose the portal and portalElement props to allow users to customize which DOM node should the tooltip render in.