export TimeSeriesTooltip to public ui

**Why is this needed**: Help provide consistent tooltip behaviour and rendering in custom plugins. **What would you like to be added**: Export TimeSeriesTooltip component to the public ui API. I would like to use this component in one of my custom plugins, but since the change to TooltipPlugin2, I am no longer able to leverage the rendering component. This was not an issue before as the legacy TooltipPlugin component encompassed the rendering too. **Who is this feature for?** This might be a specific personal requirement. Were these tooltip components always intended to be internal in the future?