[Tagging] tagging the diameter of a mini-roundabout

[Mark Reidel]

On Sat, 2023-01-28 at 09:44 +0100, Volker Schmidt wrote:
> The mm is because it's intended do describe water tubes and pipe threads,
> and not roads. That is why I have doubts using it for the mini-roundabout.

The Wiki-page for diameter explicitly mentions the use for turning_circle
and turning_loop, so I would not hesitate to apply the same logic to (mini)
roundabouts.

- Mark aka Nadjita